Herbert Macgregor 1933-2018: a personal tribute

Topsham Church and Professor Herbert Macgregor's Memorial Service

Topsham Church and the Service of Thanskgiving for the Life of Professor Herbert Macgregor

My Tribute to Professor Herbert Macgregor (22nd April 1933 – 22nd July 2018) delivered at his Thanksgiving Service on 13th August 2018

I am humbled to be here today to pay tribute to the wonderful scientist, leader and mentor, Herbert Macgregor. As a fellow cytogeneticist, Herbert has been right at the top of my field, and despite the great sadness, I am happy to be able to give you some thoughts about his remarkable and productive life. I first came across Herbert’s name in my earliest undergraduate studies with other cytogeneticists, Carl Swanson and Hugh Rees, learning of Herbert’s discovery (with Mick Callan) of the fact that each of the chromosomes within a cell nucleus – 46 of them in the case of human – contained a single DNA molecule, 100s of millions of DNA bases long, from end to end (Callan and Macgregor, 1958). Today, this is such a tenet of cell biology and genomics that it is accepted as ‘obvious’: the importance of the result supported by detailed experimental work stands equal with the other key discoveries of the late 1950s and 1960s, including the DNA helix, the genetic code, transcription, and semi-conservative replication of DNA. Herbert was a pioneer with techniques, using them and developing model systems to address many novel questions throughout his career. His book from the early 1980s, “Working with Animal Chromosomes” is still the standard reference for chromosome preparations and regularly used in my lab, while his 1993 volume, Introduction to Cytogenetics, is another standard science for interpreting chromosome form and behaviour, and appreciating its evolutionary significance.

I first met Herbert at a chromosome conference in 1982 organized in Lübeck, Germany. Herbert’s talk was a highspot of the meeting – one of those annotated with three stars in my programme. Like so many of Herbert’s papers, the title is as thoughtful and current now as when the paper was presented and written up, “The evolutionary consequences of major genomic changes”: remember this was long before the science of genomics was the huge industry that it has become. Other papers had titles such as “High resolution map” or “Application of the technique”, or discussed karyotypes and chromosome morphology. Herbert’s paper, based on his own detailed investigations of the chromosomes in one of his favoured groups, the newts and other amphibians, makes conclusions and generates ideas that are still current and important today.

Two years later, Herbert and Alma organized an important meeting of the British Society of Developmental Biology, BSDB, in Leicester, where Herbert was Professor and Head of the Department of Zoology from 1970. This was one of my first conference talks, and I remember well the exceptional organization and range of exciting talks on the topic “Genes, chromosomes and computer models in developmental biology”. At that time 34  years ago, “Computer models”  were unheard of in chromosome biology, but the contents of the volume are truly visionary. Herbert and Alma’s words in the introduction, “the frontier of this symposium lies between the biologists and computer scientists, between biology and biochemistry and mathematics and modelling” well summarize the range of Herbert’s research and its implications for the rest of his career. This 1984 meeting was my first visit to Leicester where I am now based, and there were some strange events around the conference. I remember ending up in a pub with a number of the most notable conference participants, including Adrian Bird and Chris Bostock, and witnessing still the most vicious fight I have ever seen, as well as one or two unusual conference participants!

I continued to follow with much excitement Herbert’s work, now linking gene expression with its physical manifestation as loops coming out from a special type of chromosome – lampbrush chromosomes – in amphibians and birds. This research on the arrangement and expression of DNA sequences in the genomes had major implications for molecular biology and the functioning of cell nuclei, as well as for evolution and developmental biology. Once again, this research is now part of the unquestioned canon of scientific knowledge. All through his work, from his very first papers in the late 1950s, Herbert was able to integrate microscopy with molecular biology – something that is today even more important than it was 50 years ago.

I got to know Herbert much better from the early 1990s, when he invited me to join him in a new publishing venture, setting up the Journal Chromosome Research, now in its 25th successful year. With Herbert’s vision (set out in his Macgregor1993_Article_Editorial, followed up by the insightful commentary, from 1993, on Macgregor1993_Article_ChromosomeResearchLookForwardT), it has gained a distinctive niche in a publishing area, long before the huge expansion in numbers of publications the last decade. I gained enormously from seeing his firm but helpful interactions with the series of publishers we worked through, and carefully thought-through handling of the interactions with authors and editors to build the reputation of the journal. We were now in close contact, not only with publishing but with respect to our research and the chromosome research environment. So I discussed with him about 1999 that my then institute was in an uncomfortable state of upheaval, and about any academic positions coming up? Retiring around that time, but still maintaining his lab., he asked the right people and soon after, a rather specialized advertisement appeared in a newspaper, sandwiched between adverts for the chief fire officer for B&Q (a chain of UK DIY shops), and head groundsman for the Leicester City Football Club. So I moved to Leicester, and his wise advice was so valuable to me. Most notably, Herbert valued the exceptional people he worked with, particularly among the support staff. He invariably appreciated their immense contributions, showing the importance of their roles, and the impact they could have. In this way, he was able to build an extraordinary and productive world-class Department, and I saw the remaining atmosphere he fostered in Leicester. Within the environment he fostered in his Department, he had no truck with nonsense from administrators and senior colleagues, and was forthright in his robust views. I should also add that he held the most wonderful Christmas parties, with several dozen people from the wider Department.

Herbert cared deeply about his teaching and undergraduates and gave me extremely valuable advice as I took over in teaching some of the introductory genetics and biology courses. His lecturing style was immensely approachable but still challenging, and I was not surprised to hear he continued outreach and learning activities through U3A here in Exeter. Among other things, he maintained a remarkable website here at the University of Exeter on lampbrush chromosomes, providing a resource for all – not least with its progressive CC-BY open accessibility without copyright.

Personally, it was always wonderful and memorable to meet Herbert. At the time of moving to Leicester, we stayed with him and Alma, at his farm, The Leys. He had many musical, technical and nautical interests that were always a pleasurable digression to discuss. So many characteristics of Herbert come through from every interaction I had with him, and I am very happy to have been able to pay this tribute. Hebert was, or course, very proud of his Scottish Heritage, and retained his musical accent that was so easy to listen to, carrying erudition and distinction in its tones. I do remember a meeting that ended with a Burns Night supper, where we had the privilege of hearing Herbert giving the most authentic recitation of the words of The Bard.

So I will end with some other words that are appropriate from Robbie Burns’ “Epitaph on my Own Friend”:

An honest man here lies at rest,
As e’er God with His image blest:
The friend of man, the friend of truth;
The friend of age, and guide of youth:
Few hearts like his, with virtue warm’d,
Few heads with knowledge so inform’d:
If there’s another world, he lives in bliss;
If there is none, he made the best of this.

Pat Heslop-Harrison.

Mine was one of four Tributes delivered at Professor Macgregor’s Thanksgiving Service. Others covered his early years including National Service, his Family, and life during his retirement in Topsham, Exeter.

Thanks to Dr Alma Swan, Herbert’s publication list is posted Microsoft word verstion HerbertMacgregor_PublicationList_PUBLISHED WORK  and given below:

PUBLISHED WORK OF HERBERT C. MACGREGOR 

 1958 to 2012

  1. Callan, H.G. and H.C. Macgregor (1958). Action of deoxyribonuclease on lampbrush chromosomes. Nature, 181: 1479-1480.
  2. Macgregor, H.C. (1962). The behaviour of isolated nuclei. Exp.Cell Res., 26: 520-525.
  3. Macgregor, H.C. and H.G. Callan (1962). The actions of enzymes on lampbrush chromosomes. Quart. J. Microsc. Sci.,  103:  172-203.
  4. Macgregor, H.C. (1963) Morphological variability and its physiological origin in oocyte nuclei of the crested newt. Quart.J. Microsc. Sci., 104:  351-368.
  5. Macgregor, H.C. and T.M. Uzzell (1964) Gynogenesis in salamanders related to Ambystoma jeffersonianum. Science, 143: 1043-1045.
  6. Macgregor, H.C. and P.A. Thomasson(1965). The fine structure of two archigregarines, Selenidium fallax and Ditrypanocystis cirratuli.  J.Protozool. 12:  438-443.
  7. Macgregor, H.C. (1965). The role of lampbrush chromosomes in the formation of nucleoli in amphibian oocytes. Quart. J. Microsc. Sci., 106: 215-228.
  8. Macgregor, H.C. (1965). The effects of mammalian gonadotrophins on the yolky oocytes of crested newts. Arch.Anat.Micr. 54:  652-653.
  9. Macgregor, H.C. (1967). Pattern of incorporation of 3H uridine into RNA of amphibian oocyte nucleoli. J.Cell.Sci. 2: 145-150.
  10. Macgregor, H.C. and J.B. Mackie (1967). The fine structure of the cytoplasm in salivary glands of Simulium. J. Cell. Sci. 2: 137-144.
  11. Perkowska, E., H.C. Macgregor and  M.L. Birnstiel (1968). Gene amplification in the oocyte nucleus of mutant and wild type Xenopus laevis. Nature, 217: 649-650.
  12. Walker, M. and H.C. Macgregor (1968). Spermatogenesis and the structure of the mature sperm in Nucella lapillus (L). J.Cell.Sci. 3: 95-104.
  13. Macgregor, H.C., (1968). Nucleolar DNA in oocytes of Xenopus laevis. J. Cell Sci.,  3:  437-444.
  14. Gall, J.G., H.C. Macgregor, and M.E. Kidston(1969). Gene amplification in the oocytes of dytiscid water beetles. Chromosoma, 26:169-187.
  15. Riemann, W., C. Muir, and H.C. Macgregor (1969). Sodium and potassium in oocytes of Triturus cristatus. J.Cell Sci.,  4: p. 299-304.
  16. Macgregor, H.C. (1969). Observations on the role of the germinal vesicle in amphibian and insect oogenesis. Heredity, 24: p. abstract in Proceedings of the 159th meeting of the Genetical Soc. of G.B.
  17. Macgregor, H.C. and J. Kezer (1970). Gene amplification in oocytes with 8 germinal vesicles from the tailed frog Ascaphus truei Stejneger. Chromosoma, 29: 189-206.
  18. Macgregor, H.C. and H. Stebbings (1970). A massive system of microtubules associated with cytoplasmic movement in telotrophic ovarioles. J.Cell Sci., 6: 431-449.
  19. Macgregor, H.C. and S.J. Moon (1971). Some measurements on amphibian oocyte nucleoli. Z.  Zellforsch., 122:  273-282.
  20. Kezer, J. and H.C. Macgregor (1971). A fresh look at meiosis and centromeric heterochromatin in the red-backed salamander Plethodon c. cinereus (Green). Chromosoma, 33:  146-166.
  21. Macgregor, H.C. and J. Kezer (1971). The chromosomal localisation of a heavy satellite DNA in the testis of Plethodon c. cinereus . Chromosoma, 33: 167-182.
  22. Kezer, J., H.C. Macgregor, and E. Schabtach (1971). Observations on the membranous components of amphibian oocyte nucleoli. J. Cell Sci. 8: 1-17.
  23. Macgregor, H.C. and M. Vlad (1972). Interlocking and knotting of ring nucleoli in amphibian oocytes. Chromosoma, 39: 205-214.
  24. Macgregor, H.C. (1972). The nucleolus and its genes in amphibian oogenesis. Biol.Rev. 47: 177-210.
  25. Macgregor, H.C. (1973). Amplification, polytenisation and nucleolus organisers. Nature New Biology, 246: 81-82.
  26. Macgregor, H.C., H.A. Horner, C.A. Owen and I. Parker (1973). Observations on centromeric heterochromatin and satellite DNA in salamanders of the genus Plethodon. Chromosoma, 43: 329-348.
  27. Macgregor, H.C. and M. Walker (1973). The arrangement of chromosomes in nuclei of sperm from plethodontid salamanders. Chromosoma, 40: 243-262.
  28. Macgregor, H.C. and J. Kezer (1973). The nucleolar organiser of Plethodon c. cinereus. I. Location of the organiser by in-situ nucleic acid hybridisation. Chromosoma, 42:  415-426.
  29. Kezer, J. and H.C. Macgregor (1973). The nucleolar organiser of Plethodon c. cinereus. II. The lampbrush nucleolar organizer. Chromosoma, 42: 427-444.
  30. Walker, M.H. and H.C. Macgregor (1974). The arrangement of chromosomes in elongate sperm heads. in  Chromosomes Today, 5 :  13 – 22.  (John Wiley & Sons).
  31. Mizuno, S. and H.C. Macgregor (1974). Chromosomes, and sequences and evolution in salamanders of the genus Plethodon. Chromosoma, 48: p. 239-296.
  32. Macgregor, H.C., S. Mizuno, and M. Vlad. Some recent studies on chromosomes and DNA sequences in salamanders. in Chromosomes Today 5 : 331 – 339. (John Wiley & Sons).
  33. Vlad, M. and H.C. Macgregor (1975). Chromomere number and its genetic significance in lampbrush chromosomes. Chromosoma, 50: 327-347.
  34. Hennen, S., S. Mizuno, and H.C. Macgregor (1975). In-situ hybridisation of rDNA labelled with 125-I to metaphase and lampbrush chromosomes of newts. Chromosoma, 50:340-360.
  35. Macgregor, H.C., M. Vlad, and L. Barnett (1976). An investigation of some problems concerning nucleolus organisers in salamanders. Chromosoma, 59: 283-299.
  36. Macgregor, H.C. and S. Mizuno (1976). In-situ hybridisation of ‘nick-translated’ 3H-ribosomal DNA to chromosomes from salamanders. Chromosoma, 54:  15-25.
  37. Mizuno, S., C. Andrews, and H.C. Macgregor (1976) Interspecific ‘common’ DNA sequences in salamanders of the genus Plethodon. Chromosoma, 58: 1-31.
  38. Macgregor, H.C. and C. Andrews (1977). The arrangement and transcription of ‘middle repetitive’ DNA sequences on lampbrush chromosomes of Triturus. Chromosoma, 63: 109-126.
  39. Macgregor, H.C. (1977). Lampbrush Chromosomes. in Chromatin and Chromosome Structure., R.A. Eckhardt and Hseuh-Jei Li (Editors). pp. 339 – 357.  Academic Press:
  40. Macgregor, H.C. and C. Jones (1977). Chromosomes, DNA sequences, and evolution in salamanders of the genus Aneides. Chromosoma, 63: 1-9.
  41. Macgregor, H.C. and G.T. Morgan (1978). Repetitive DNA and chiasma failure in chromosome I of crested newts. J.Cell Biol., 79: 133a. (Abstract)
  42. Macgregor, H.C. (1978). Trends in the evolution of very large chromosomes. Proc.Roy.Soc.London, B 283: 309-318.
  43. Morgan, G.T., H.C. Macgregor, and A. Colman (1979). Multiple ribosomal sites revealed by in situ hybridisation of Xenopus  rDNA to Triturus  lampbrush chromosomes. Chromosoma,   80: 309-330.
  44. Macgregor, H.C. and S. Sherwood (1979). The nucleolus organisers of Plethodon and Aneides  located by in-situ  nucleic acid hybridisation with Xenopus  3H ribosomal RNA. Chromosoma, 72:  271-280.
  45. Macgregor, H.C. (1979). In-situ hybridisation of highly repetitive DNA to chromosomes of Triturus cristatus. Chromosoma, 71:  57-64.
  46. Macgregor, H.C. and L. Klosterman (1979). Observations on the cytology of Bipes (Amphisbaenia) with special reference to its lampbrush chromosomes. Chromosoma, 72: 67-87.
  47. Macgregor, H.C. (1980). Recent developments in the study of lampbrush  chromosomes. Heredity, 44: 3-35.
  48. Varley, J.M., H.C. Macgregor, and H.P. Erba (1980). Satellite DNA is transcribed on lampbrush chromosomes. Nature, 283:  686-688.
  49. Hill, R.S. and Macgregor, H.C. (1980). The development of lampbrush chromosome-type transcription in the early diplotene oocytes of Xenopus laevis: an electron microscope analysis.  J. Cell Sci.  44, 87 – 101.
  50. Macgregor, H.C., J.M. Varley, and G.T. Morgan (1981). The transcription of satellite and ribosomal DNA sequences on lampbrush chromosomes of crested newts., in International Cell Biology. Springer-Verlag: p. 33-46.
  51. Macgregor, H.C. and H.A. Horner (1980). Heteromorphism for chromosome I, a requirement for normal development in crested newts. Chromosoma, 76: 111-122.
  52. Macgregor, H.C. (1980). Recent developments in the study of lampbrush chromosomes. Heredity, 44:  3-35.
  53. Varley, J. M., H.C. Macgregor,  I. Nardi,  C. Andrews and H.P. Erba (1980). Transcription of highly repeated DNA sequences during the lampbrush stage in Triturus cristatus carnifex. Chromosoma, 80: 289-307.
  54. Macgregor, H.C. (1982). Big chromosomes and speciation amongst Amphibia.  in Genome Evolution, G.A. Dover and R.B. Flavell (Editors). Academic Press: pp. 325-341.
  55. Macgregor, H.C. (1982). Ways of amplifying ribosomal genes.  in  The Nucleolus.  Society for Experimental Biology Seminar Series 15, E.G. Jordan and C.A. Cullis (Editors). Cambridge University Press: Cambridge. pp. 129-152.
  56. Macgregor, H.C. and E. del Pino (1982). Ribosomal gene amplification in  ultinucleate oocytes of the egg brooding hylid frog Flectonotus pygmaeus. Chromosoma, 85:  475-488.
  57. Horner, H.A. and H.C. Macgregor (1983). C value and cell volume; their significance in the evolution and development of amphibians. J.Cell Sci., 63: 135-146.
  58. Macgregor, H.C. and J.M. Varley (1983). Working with Animal Chromosomes. John Wiley and Sons Ltd.: Chichester and New York.
  59. Macgregor, H.C., Horner, H.A. and Sims, S.H. (1983). Newt chromosomes and some problems in evolutionary cytogenetics.  Proceedings of the Kew Chromosome Conference II, Allen and Unwin.  pp. 283 – 294.
  60. Swan, A.P., H.C. Macgregor, and R. Ransom (editors) (1984). Programmes for Development.  Symposium of the British Society for Developmental Biology. 1984. The Company of Biologists.
  61. Macgregor, H.C. (1984). The lampbrush chromosomes of animal oocytes.  in Chromosome Structure and Function, M. Risley, (Editor). van Rostrand and Reinhold Publishing Corp: New York. pp. 152 – 186.
  62. Macgregor, H.C. and A.P. Swan (1984). An introduction to Programmes for Development. J.Embryol.Exp.Morph. 83(Supplement):  1-6.
  63. Sims, S.H., H.C. Macgregor, P.A. Pellatt and H.A. Horner (1984). Chromosome 1 in crested and marbled newts genus Triturus: an extraordinary case of  heteromorphism and independent chromosome evolution. Chromosoma, 89: 169-185.
  64. Macgregor, H.C. (1984). Lampbrush chromosomes and gene utilisation in meiotic prophase. In Controlling Events in Meiosis, W. Evans and H.G.Dickinson (Editors).  The Company of Biologists. pp. 333 – 348.
  65. Macgregor, H.C. (1984). The evolutionary consequence of major genomic changes in Amphibia. In Chromosomes Today, 8 M.D.Bennett, A. Gropp, U. Wolf (Editors).  George Allen and Unwin.  pp. 256 – 267.
  66. Horner, H.A. and H.C. Macgregor (1985). Normal development in newts (Triturus) and its arrest as a consequence of an unusual chromosomal situation.  J. Herpetology, 19:  216 – 270.
  67. Baldwin, L. and H.C. Macgregor (1985). Centromeric satellite DNA in the newt Triturus cristatus karelinii and related species: its distribution and transcription on lampbrush chromosomes. Chromosoma, 92: 100-107.
  68. Macgregor, H.C. and S.K. Sessions (1986). The biological significance of variation in satellite DNA and heterochromatin in newts of the genus Triturus: an evolutionary perspective., in The Evolution of DNA Sequences, B.C. Clarke, A. Robertson and A.J. Jeffreys (Editors). Phil. Trans. R. Soc. Lond.: B 312:  53 – 70.
  69. Macgregor, H.C. (1986). Care, maintenance and captive breeding of newts (Triturus).  In UFAW Handbook, Longman.  pp. 768 – 772.
  70. Schmid, M., S.H. Sims, T. Haaf and H.C. Macgregor (1986). Chromosome banding in Amphibia X. 18S and 28S ribosomal RNA genes, nucleolus organizers and nucleoli in Gastrotheca riobambae .   Chromosoma, 94:  139-145.
  71. Macgregor, H.C. and S.K. Sessions (1986). Models for evolution of large genomes and karyotypes of urodeles. Verhandlungen der Duetzchen Zoologischen Gesellschaft., 79: 137-148.
  72. Macgregor, H.C. (1986). The lampbrush chromosomes of animal oocytes. in Chromosome Structure and Function, M.Risley (Editor), Van Rostrand & Reinhold Publishing Corporation, New York.: pp. 152-186.
  73. Macgregor, H.C. (1987). Lampbrush Chromosomes. J. Cell. Sci. 88: 7-9.
  74. Macgregor, H.C. (1988). The Evolutionary Cytogenetics of Triturus (Amphibia, Urodela):  An overview. In Symposium on the Evolution of Terrestrial Vertebrates, G. Chiara (Editor).  Mucchi, Modena.  pp. 153 – 170.
  75. Macgregor, H.C. and J. Varley (1988). Working with Animal Chromosomes. 2nd edition. John Wiley & Sons.
  76. Macgregor, H.C. (1988). Chromosome heteromorphism in newts (Triturus) and its significance in in relation to evolution and development. In Amphibian Cytogenetics and Evolution, D. Green and S.K.Sessions (Editors). Academic Press.  pp. 175 – 196.
  77. Sessions, S.K., H.C. Macgregor, M. Schmid and T. Haaf (1988). Cytology, embryology and evolution of the developmental arrest syndrome in newts of the genus Triturus (Caudata: Salamandridae).  J. exp. Zool.  248:  321 – 334.
  78. Macgregor, H.C. (1990). Newts and two studies in molecular cytogenetics., in Cytogenetics of Amphibians and Reptiles, E. Olmo (Editor).  Birkhauser Verlag. pp. 61-84.
  79. Varley, J.M., H.C. Macgregor and L. Barnett (1990). Characterization of a short, highly repeated and centromerically localized DNA sequence in crested and marbled newts of the genus Triturus.  Chromosoma, 100:  15 – 31.
  80. Macgregor, H.C., S.K. Sessions, and J.W. Arntzen (1990). An integrative analysis of phylogenetic relationships amongst newts of the genus Triturus (family Salamandridae) using comparative biochemistry, cytogenetics and reproductive interactions. J.Evol.Biol. 3:  329-374.
  81. Solovei, I., E. Gaginskaya, T.D. Allen and H.C. Macgregor (1992). A novel structure associated with a lampbrush chromosome in the chicken, Gallus domesticus. J. Cell Science, 101: 759-772.
  82. Macgregor, H.C. (1992). Introduction to Biological Sciences. in The Pergamon Encyclopedia for Higher Education. 4:  2181 – 2183.  Pergamon Press, Oxford.
  83. Macgregor, H.C. (1992). Evolutionary Biology. In Pergamon Encyclopedia for Higher Education, 4: 2226 – 2231.  Pergamon Press, Oxford.
  84. Solovei, I., E. Gaginskaya, N. Hutchison and H.C. Macgregor  (1993).  Avian sex chromosomes in the lampbrush form:  the ZW lampbrush bivalents from six species of bird. Chromosome Research, 1:  153-166.
  85. Macgregor, H.C. (1993). British Universities in the World of Business. The New Academic, 3:  12-14.
  86. Macgregor, H.C. (1993). An Introduction to Animal Cytogenetics. Chapman and Hall: London.
  87. Macgregor, H.C. (1993). Chromosome Research – look forward to 2001.  Chromosome Research, 1: 5-7
  88. Solovei, I., E.R. Gaginskaya, and H.C. Macgregor (1994). The arrangement and transcription of telomere DNA sequences at the ends of lampbrush chromosomes of birds. Chromosome Research, 2: 460-470.
  89. Fairchild, P.J., Macgregor H.C. (1994). Asymmetric loops. Current Biology, 4: 919.
  90. Solovei, I., H.C. Macgregor and E. Gaginskaya (1995). Single stranded nucleic acid binding structures on chicken lampbrush chromosomes.  J. Cell Sci.  108, 1391 – 1396.
  91. Solovei, I., H.C. Macgregor and E. Gaginskaya (1995). Specifically terminal clusters of telomere DNA sequences are transcribed from the C-rich strand on chicken lampbrush chromosomes.  Proc. Kew Chromosome Conference IV.  P.F.Brandham and M.D.Bennett (eds. Royal Botanic Gardens, Kew, Press. 1995.  pp.  323 – 330.
  92. Macgregor, H.C. (1995). Crested Newts: Ancient Survivors.  British Wildlife 7:  1 – 8.
  93. Macgregor, H.C. (2011). From Bones to Biotechnology: 50 years of new biology in the Old World.   In A History of the University in Europe (ed. Walter Ruegg) Volume IV, 451 – 471. Cambridge University Press.
  94. Hori, T., Susuki, Y., Solovei, I., Saitoh, Y., Hutchison, N., Ikeda, Joh-E., Macgregor, H.C., Mizuno, S. (1996). Characterization of DNA sequences constituting the terminal heterochromatin of the chicken Z chromosome. Chromosome Research  4 :  411 – 426.
  95. Joffe, B.I., Solovei, I. V., Macgregor, H.C. (1996) Ends of chromosomes in Polycelis tenuis (Platyhelminthes) have telomere repeat TTAGGG. Chromosome Research  4:  323-324.
  96. Macgregor H.C., Solovei I., and Mizuno, S. (1997)  Lampbrush chromosomes as systems for high resolution studies of meiotic chromosome structure.  in  Chromosome Segregation and Aneuploidy, (ed. A. Abbondandolo, B.K.Vig and R. Roi). European Commission Joint Research Centre Publication. pp 172 – 183.
  97. Solovei, I., Joffe, B. Gaginskaya, E., Macgregor, H.C. (1996) Transcription on lampbrush chromosomes of a centromerically localized highly repeated DNA in pigeon (Columba) relates to sequence arrangement. Chromosome Research 4, 588 – 603.
  98. Ogawa, A., Solovei, I., Hutchison, N., Saitoh, Y., Ikeda, J-E., Macgregor, H.C., Mizuno, S. (1997).  Molecular characterization and cytological mapping of a non-repetitive DNA sequence region from the W chromosome of chicken and its use as a universal probe for sexing Carinatae birds.  Chromosome Research  5,  93 – 101.
  99. Joffe, B., Solovei, I., Macgregor,  H.C. (1998)  Ordered arrangement and rearrangement of chromosomes during spermatogenesis in two species of planarians (Platyhelminthes).  Chromosoma 107, 173 – 183.
  100. Solovei, I., Joffe, B., Hori, T., Thomson, P., Mizuno, S., Macgregor, H.C. (1998) Unordered arranmgement of chromosomes in nuclei of chicken spermatozoa. Chromosoma  107,  184 – 188.
  101. Mizuno, S., Macgregor H.C. (1998) The ZW lampbrush chromosomes of birds: a unique opportunity to look at the molecular cytogenetics of sex chromosomes.  Cytogenet. Cell Genet. 80, 149 – 157.
  102. Solovei, I., Ogawa, A., Naito, M., Mizuno, S., Macgregor H.C. (1998) Specific chromomeres on the chicken W lampbrush chromosome contain specific repetitive DNA sequence families. Chromosome Research  6, 323 – 327.
  103. Baker, S., Greig, C., Macgregor, H.C., Swan, A. (1998) Exmoor ponies:  Britain’s prehistoric wild horses?  British Wildlife  9, 304 – 313.
  104. Macgregor, H.C. (2000) The Future of Chromosomes. In Chromosomes Today, (E. Olmo and C.A.Redi, eds.) 13, 305 – 313.  Birkhauser Verlag.
  105. Teranishi, M., Shimada, Y., Hori, T., Nakabayashi, O., Kikuchi, T., MacLeod, T., Pym, R., Sheldon, B., Solovei, I., Macgregor, H.C., Mizuno, S. (2001) Transcripts of the MHM region on the chicken Z chromosome accumulate as non-coding RNA in the nucleus of female cells adjacent to the DMRT1 locus. Chromosome Research, 9: 147 – 165.
  106. Sessions, S.K., Macgregor, H.C. (2009) The necessity of Darwin. Chromosome Research 17: 437 – 442.
  107. Macgregor, H.C. (2012) Chromomeres revisited. Chromosome Research 20: 911 – 924.
  108. Macgregor, H.C. (2012) So what’s so special about these things called lampbrush chromosomes? Chromosome Research 20: 903 – 904.

 

 

Edits 14/8/18: hyperlinks, explain B&Q as shop.

Edit 10/9/18: Publication List for Professor HC Herbert Macgregor added

 

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Complete mitogenomes from Kurdistani sheep – abundant centromeric nuclear copies representing diverse ancestors

Kurdistani sheep breeds and part of their mitochondrial genome From Mustafa et al. Mitochondrial DNA part A 2018.

Kurdistani sheep breeds and part of their mitochondrial genome From Mustafa et al. Mitochondrial DNA part A 2018.

341. Mustafa SI, Schwarzacher T, and Heslop-Harrison JS. 2018. Complete mitogenomes from Kurdistani sheep: abundant centromeric nuclear copies representing diverse ancestorsMitochondrial DNA Part A https://doi.org/10.1080/24701394.2018.1431226 (publisher – see free publisher link below if you can’t access) AND Mustafa et al_2018 AuthorVersion

The geographical center of domestication and species diversity for sheep (Ovis aries) lies around the Kurdistan region of Northern Iraq, within the ‘Fertile Crescent’. From whole genome sequence reads, we assembled the mitochondrial genomes (mtDNA or mitogenome) of five animals of the two main Kurdistani sheep breeds Hamdani and Karadi and found they fitted into known sheep haplogroups (or matrilineages), with some SNPs. Haplotyping 31 animals showed presence of the main Asian (hpgA) and European (hpgB) haplogroups, as well as the rarer Anatolian haplogroup hpgC. From the sequence reads, near-complete genomes of mitochondria from wild sheep species (or subspecies), and even many sequences similar to goat (Capra) mitochondria, could be extracted. Analysis suggested that these polymorphic reads were nuclear mitochondrial DNA segments (numts). In situ hybridization with seven regions of mitochondria chosen from across the whole genome showed strong hybridization to the centromeric regions of all autosomal sheep chromosomes, but not the Y. Centromeres of the three submetacentric pairs and the X chromosomes showed fewer copies of numts, with varying abundance of different mitochondrial regions. Some mitochondrial-nuclear transfer presumably occurred before species divergence within the genus, and there has been further introgression of sheep mitochondrial sequences more recently. This high abundance of nuclear mitochondrial sequences is not reflected in the whole nuclear genome assemblies, and the accumulation near major satellite sequences at centromeres was unexpected. Mitochondrial variants including SNPs, numts and heteroplasmy must be rigorously validated to interpret correctly mitochondrial phylogenies and SNPs.

Keywords: nuclear mitochondrial DNA segments (numts); mitogenome diversity; massively parallel sequencing; fluorescent in situ hybridization; sheep domestication

Free link to paper from publishers: http://www.tandfonline.com/eprint/YSxE33mSJiBMVEuMXIyv/full (limited to 50 uses so please look at author version first or use your academic library link via DOI below!)

341. Mustafa SI, Schwarzacher T, and Heslop-Harrison JS. 2018. Complete mitogenomes from Kurdistani sheep: abundant centromeric nuclear copies representing diverse ancestorsMitochondrial DNA Part A https://doi.org/10.1080/24701394.2018.1431226 () Mustafa et al_2018 AuthorVersion

 

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Morphology, adaptation and speciation

Plant adaptation arises from their morphology, itself a product of evolution and development. In this figure, the aspects and interactions of research at different levels are shown, with the work having implications across botany, including understanding plant phylogeny and speciation, and for ecology and ecosystems.

Plant adaptation arises from their morphology, itself a product of evolution and development. In this figure, the aspects and interactions of research at different levels are shown, with the work having implications across botany, including understanding plant phylogeny and speciation, and for ecology and ecosystems.

Heslop-Harrison JS. 2017. Morphology, adaptation and speciation. Annals of Botany 120(7): 621-624. https://doi.org/10.1093/aob/mcx130The study of plant evolution and development in a phylogenetic context has accelerated research advances in both areas over the last decade. The addition of a robust phylogeny for plant taxa based on DNA as well as morphology has given a strong context for this research. Genetics and genomics, including sequencing of many genes, and a better understanding of non-genetic, responsive changes, by plants have increased knowledge of how the different body forms of plants have arisen. Here, I overview the papers in this Special Issue of Annals of Botany on Morphological Adaptation, bringing together a range of papers that link phylogeny and morphology. These lead to models of development and functional adaptation across a range of plant systems, with implications for ecology and ecosystems, as well as development and evolution.

The study of evolution and development (evo-devo) has advanced plant research including speciation (Fernández-Mazuecos and Glover 2017); and as Theodore Dobzhansky stated in 1973, ‘nothing makes sense except in the light of evolution’. But what options are there for plant architecture to evolve – from the gene to cellular to organ and on to whole plant and ecosystem level? As suggested in the mind-map of Fig. 1, we are now in a good position to exploit data from morphological and genetic studies to understand the key processes of evolution and development, taking those results to find their impact on ecology and ecosystems. The papers in this special issue cover a diverse range of species, organs (related to leaves, roots and flowers) and approaches (from advanced microscopy to DNA fingerprinting), to show how modern plant studies can be integrated to lead to models of evolution and understand plant development in the broadest context.

 

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Crop Improvement – Plant Nuclear Genomes

328. Heslop-Harrison JS. 2017. Crop Improvement: Plant Nuclear Genomes. Encyclopedia of Applied Plant Sciences 2nd Edition. In proof.

Plant breeders work with large amounts of DNA sequence information including the sequences of all genes and the repetitive DNA that makes up the majority of most genomes. Knowledge of the diversity and evolution of the sequences is proving important to developing DNA markers, indentifying genetic and QTL characters, the selection of breeding lines and the measurement and exploitation of biodiversity. Nuclear DNA sequence information can be used for improvement all crop species with directed superdomestication approaches leading to improved performance, resistances to biotic and abiotic stress, and greater environmental sustainability to meet the challenges of increasing populations and climate change.

Keywords

Biodiversity, Breeding, Epigenetics, Genetics, Genomics, Genomes, Repetitive DNA, Traits, Plastomes, Chloroplasts, Markers, QTL, Chromosomes, Genome size

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Repetitive DNA in the catfish genome- rDNA, microsatellites, and Tc1-mariner transposon sequences in Imparfinis

Repetitive sequence organization on chromosomes of a Brazilian catfish species, important for understanding their evolution and biodiversity. Gouveia et al., Journal of Heredity, 2017.

Repetitive sequence organization on chromosomes of a Brazilian catfish species, important for understanding their evolution and biodiversity. Gouveia et al., Journal of Heredity, 2017.

339. Gouveia JG, Wolf IR, Vilas-Boas LA, Heslop-Harrison JS, Schwarzacher T, Dias AL. 2017. Repetitive DNA in the catfish genome: rDNA, microsatellites, and Tc1-mariner transposon sequences in Imparfinis species (Siluriformes, Heptapteridae). Journal of Heredity 108(6): 650-657.

Journal link: https://doi.org/10.1093/jhered/esx065 Author PHHGouveia_CatfishRepeatsAuthorVersion

Physical mapping of repetitive DNA families in the karyotypes of fish is important to understand the organization and evolution of different orders, families, genera, or species. Fish in the genus Imparfinis show diverse karyotypes with various diploid numbers and ribosomal DNA (rDNA) locations. Here we isolated and characterized Tc1-mariner nucleotide sequences from Imparfinis schubarti, and mapped their locations together with 18S rDNA, 5S rDNA, and microsatellite probes in Imparfinis borodini and I.  schubarti chromosomes. The physical mapping of Tc1/Mariner on chromosomes revealed dispersed signals in heterochromatin blocks with small accumulations in the terminal and interstitial regions of I. borodini and I. schubarti. Tc1/Mariner was coincident with rDNA chromosomes sites in both species, suggesting that this transposable element may have participated in the dispersion and evolution of these sequences in the fish genome. Our analysis suggests that different transposons and microsatellites have accumulated in the I. borodini and I.  schubarti genomes and that the distribution patterns of these elements may be related to karyotype evolution within Imparfinis.

Subject area: Genomics and gene mapping
Key words: genome evolution, karyotype evolution, MITEs, transposable elements

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Polyploidy and interspecific hybridisation: partners for adaptation, speciation and evolution in plants

337. Alix K, Gérard PR, Schwarzacher T, Heslop-Harrison JS. 2017. Polyploidy and interspecific hybridisation: partners for adaptation, speciation and evolution in plants. Annals of Botany 120(2): 183-194. https://doi.org/10.1093/aob/mcx079  (Free access).

Polyploidy, defined as whole genome duplication, is present in almost all lineages of higher plants, with multiple rounds of polyploidy occurring in most extant species. This Annals of Botany Special Issue on Polyploidy in Ecology and Evolution presents the evolutionary consequences of new, recent, and ancient polyploidy. Alix et al. survey experimental, genomic, ecological and theoretical studies demonstrating that polyploidization often occurs during periods of major evolutionary transitions and adaptive radiation of species. Polyploidy, the cornerstone of bursts of adaptive speciation, brings about genetic novelty. The emergence of new gene functions enables diversification, speciation, and hence plant evolution.

The figure can be downloaded in Powerpoint format here AlixSchwarzacherHeslopHarrisonPlantEvolutionPolyploidyWGDAnnalsBotany format.

Background Polyploidy or whole genome duplication is now recognized as being
present in almost all lineages of higher plants, with multiple rounds of polyploidy
occurring in most extant species. The ancient evolutionary events have been identified through genome sequence analysis, while recent hybridisation events are found in about half of the world’s crops and wild species. Building from this new paradigm for understanding plant evolution, the papers in this Special Issue address questions about polyploidy in ecology, adaptation, reproduction and speciation of wild and cultivated plants from diverse ecosystems. Other papers, including this article, consider genomic aspects of polyploidy.
• Approaches Discovery of the evolutionary consequences of new, evolutionarily
recent, and ancient polyploidy requires a range of approaches. Large scale studies of
both single species, and whole ecosystems, with hundreds to tens of thousands of
individuals, sometimes involving ‘garden’ or transplant experiments are important for studying adaptation. Molecular studies of genomes are needed to measure diversity in genotypes, showing ancestors, the nature and number of polyploidy and backcross events that have occurred, and allowing analysis of gene expression and transposable element activation. Speciation events and the impact of reticulate evolution, require comprehensive phylogenetic analyses and can be assisted by resynthesis of hybrids. In this Special Issue, we include studies ranging in scope from experimental and genomic, through ecological to more theoretical.
• Conclusions The success of polyploidy, displacing the diploid ancestors of almost all
plants, is well illustrated by the huge angiosperm diversity that is assumed to originate from recurrent polyploidisation events. Strikingly, polyploidisation often occurred prior to or simultaneously with major evolutionary transitions and adaptive radiation of species, supporting that concept that polyploidy plays a predominant role in bursts of adaptive speciation. Polyploidy results in immediate genetic redundancy and represents, with the emergence of new gene functions, an important source of novelty. Along with recombination, gene mutation, transposon activity and chromosomal rearrangement, polyploidy and whole genome duplication act as a driver of evolution and divergence in plant behaviour and gene function, enabling diversification, speciation and hence plant evolution.

Key words: Polyploidy, hybrids, ecology, adaptation, evolution, genomics, chromosomes, speciation, whole genome duplication (WGD), crops, weeds, phylogeny, bryophytes,
angiosperms

Published version: https://doi.org/10.1093/aob/mcx079  (Free access).

And

AlixPolyploidy2017AuthorVersion.

 

Update 16/8/2017 to add author version (although original is free acces) and page reference.

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Identification and characterization of mobile genetic elements LINEs from Brassica genome

Nouroz F, Noreen S, Khan MF, Ahmed S, Heslop-Harrison JS. 2017. Identification and characterization of mobile genetic elements LINEs from Brassica genomes. Gene 627: 94-105. doi: 10.1016/j.gene.2017.06.015..

Abstract
Among transposable elements (TEs), the LTR retrotransposons are abundant followed by nonLTR retrotransposons in plant genomes, the lateral being represented by LINEs and SINEs. Computational and molecular approaches were used for the characterization of Brassica LINEs, their diversity and phylogenetic relationships. Four autonomous and four nonautonomous LINE families were identified and characterized from Brassica. Most of the autonomous LINEs displayed two open reading frames, ORF1 and ORF2, where ORF1 is a gag protein domain, while ORF2 encodes endonuclease (EN) and a reverse transcriptase (RT). Three of four families encoded an additional RNase H (RH) domain in pol gene common to ‘R’ and ‘I’ type of LINEs. The PCR analyses based on LINEs RT fragments indicate their high diversity and widespread occurrence in tested 40 Brassica cultivars. Database searches revealed the homology in LINE sequences in closely related genera Arabidopsis indicating their origin from common ancestors predating their separation. The alignment of 58 LINEs RT sequences from Brassica, Arabidopsis and other plants depicted 4 conserved domains (domain II-V) showing similarity to previously detected domains. Based on RT alignment of Brassica and 3 known LINEs from monocots, Brassicaceae LINEs clustered in separate clade, further resolving 4 Brassica-Arabidopsis specific families in 2 sub-clades. High similarities were
observed in RT sequences in the members of same family, while low homology was detected in members across the families. The investigation led to the characterization of Brassica specific LINE families and their diversity across Brassica species and their cultivars.

Keywords: Retrotransposons, Brassica, LINEs, Reverse transcriptase, Diversity, Phylogeny.

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