Skip to main content
SpringerLink
Log in

Sex chromosomes, synapsis, and cohesins: a complex affair

  • Review
  • Published:
Chromosoma Aims and scope Submit manuscript

Abstract

During first meiotic prophase, homologous chromosomes are held together by the synaptonemal complex, a tripartite proteinaceous structure that extends along the entire length of meiotic bivalents. While this feature is applicable for autosomes, sex chromosomes often escape from this rule. Many species present sex chromosomes that differ between them in their morphology, length, and gene content. Moreover, in some species, sex chromosomes appear in a single dose in one of the sexes. In all of these cases, the behavior of sex chromosomes during meiosis is conspicuously affected, and this includes the assembly and dynamics of the synaptonemal complex. We review in this study the structure of the synaptonemal complex in the sex chromosomes of three groups of organisms, namely: mammals, orthopterans, and hemipterans, which present different patterns of sex chromosome structure and behavior. Of special interest is the analysis of the organization of the axial/lateral elements of the synaptonemal complex in relation to other axial structures organized along meiotic chromosomes, mainly the cohesin axis. The differences found in the behavior of both axial structures reveal that while the organization of a cohesin axis along sex chromosomes is a conserved feature in most organisms and it shows very little morphological variations, the axial/lateral elements of the synaptonemal complex present a wide range of structural modifications on these chromosomes.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

References

  • Alsheimer M, Imamichi Y, Heid H, Benavente R (1997) Molecular characterization and expression pattern of XY body-associated protein XY40 of the rat. Chromosoma 106:308–314

    Article  PubMed  CAS  Google Scholar 

  • Ayoub N, Richler C, Wahrman J (1997) Xist RNA is associated with the transcriptionally inactive XY body in mammal male meiosis. Chromosoma 106:1–10

    Article  PubMed  CAS  Google Scholar 

  • Bellani MA, Romanienko PJ, Cairatti DA, Camerini-Otero RD (2005) SPO11 is required for sex-body formation, and Spo11 heterozygosity rescues the prophase arrest of Atm−/− spermatocytes. J Cell Sci 118:3233–3245

    Article  PubMed  CAS  Google Scholar 

  • Calvente A, Viera A, Page J, Parra MT, Gomez R, Suja JA, Rufas JS, Santos JL (2005) DNA double-strand breaks and homology search: inferences from a species with incomplete pairing and synapsis. J Cell Sci 118:2957–2963

    Article  PubMed  CAS  Google Scholar 

  • Carnero A, Jimenez R, Burgos M, Sanchez A, Diaz de la Guardia R (1991) Achiasmatic sex chromosomes in Pitymys duodecimcostatus: mechanisms of association and segregation. Cytogenet Cell Genet 56:78–81

    Article  PubMed  CAS  Google Scholar 

  • Charlesworth B (1991) The evolution of sex chromosomes. Science 251:1030–1033

    Article  PubMed  CAS  Google Scholar 

  • Charlesworth D (2002) Plant sex determination and sex chromosomes. Heredity 88:94–101

    Article  PubMed  Google Scholar 

  • Counce SJ, Meyer GF (1973) Differentiation of the synaptonemal complex and the kinetochore in Locusta spermatocytes studied by whole mount electron microscopy. Chromosoma 44:231–253

    Article  PubMed  CAS  Google Scholar 

  • del Mazo J, Gil-Alberdi L (1986) Multistranded organization of the lateral elements of the synaptonemal complex in the rat and mouse. Cytogenet Cell Genet 41:219–224

    Article  PubMed  Google Scholar 

  • Dietrich AJ, van Marle J, Heyting C, Vink AC (1992) Ultrastructural evidence for a triple structure of the lateral element of the synaptonemal complex. J Struct Biol 109:196–200

    Article  PubMed  CAS  Google Scholar 

  • Dobson MJ, Pearlman RE, Karaiskakis A, Spyropoulos B, Moens PB (1994) Synaptonemal complex proteins: occurrence, epitope mapping and chromosome disjunction. J Cell Sci 107:2749–2760

    PubMed  CAS  Google Scholar 

  • Earnshaw WC, Halligan B, Cooke CA, Heck MM, Liu LF (1985) Topoisomerase II is a structural component of mitotic chromosome scaffolds. J Cell Biol 100:1706–1715

    Article  PubMed  CAS  Google Scholar 

  • Eijpe M, Heyting, C, Gross B, Jessberger R (2000) Association of mammalian SMC1 and SMC3 proteins with meiotic chromosomes and synaptonemal complex. J Cell Sci 113:673–682

    PubMed  CAS  Google Scholar 

  • Eijpe M, Offenberg H, Jessberger R, Revenkova E, Heyting C (2003) Meiotic cohesin REC8 marks the axial elements of rat synaptonemal complexes before cohesins SMC1beta and SMC3. J Cell Biol 160:657–670

    Article  PubMed  CAS  Google Scholar 

  • Escalier D, Garchon HJ (2000) XMR is associated with the asynapsed segments of sex chromosomes in the XY body of mouse primary spermatocytes. Chromosoma 109:259–265

    Article  PubMed  CAS  Google Scholar 

  • Fawcett DW (1956) The fine structure of chromosomes in the meiocyte prophase of vertebrate spermatocyte. J Biophys Biochem Cytol 2:403–406

    PubMed  CAS  Google Scholar 

  • Fernandez-Capetillo O, Mahadevaiah SK, Celeste A, Romanienko PJ, Camerini-Otero RD, Bonner WM, Manova K, Burgoyne P, Nussenzweig A (2003) H2AX is required for chromatin remodeling and inactivation of sex chromosomes in male mouse meiosis. Dev Cell 4:497–508

    Article  PubMed  CAS  Google Scholar 

  • Fraser JA, Heitman J (2005) Chromosomal sex-determining regions in animals, plants and fungi. Curr Opin Genet Dev 15:645–651

    Article  PubMed  CAS  Google Scholar 

  • Goetz P, Chandley AC, Speed RM (1984) Morphological and temporal sequence of meiotic prophase development at puberty in the male mouse. J Cell Sci 65:249–263

    PubMed  CAS  Google Scholar 

  • Gonzalez-Garcia JM, Antonio C, Suja JA, Rufas JS (1986) Meiosis in holocentric chromosomes: kinetic activity is randomly restricted to the chromatid ends of sex univalents in Graphosoma italicum (Heteroptera). Chromosome Res 4:124–132

    Article  Google Scholar 

  • Graves JAM (1996) Mammals that break the rules: genetics of marsupials and monotremes. Annu Rev Genet 30:233–260

    Article  PubMed  CAS  Google Scholar 

  • Handel MA (2004) The XY body: a specialized meiotic chromatin domain. Exp Cell Res 296:57–63

    Article  PubMed  CAS  Google Scholar 

  • Hayman DL (1990) Marsupial cytogenetics. Aust J Zool 37:331–349

    Article  Google Scholar 

  • Heyting C (2005) Meiotic transverse filament proteins: essential for crossing over. Transgenic Res 14:547–550

    Article  PubMed  CAS  Google Scholar 

  • Heyting C, Moens PB, van Raamsdonk W, Dietrich AJ, Vink AC, Redeker EJ (1987) Identification of two major components of the lateral elements of synaptonemal complexes of the rat. Eur J Cell Biol 43:148–154

    PubMed  CAS  Google Scholar 

  • Hoyer-Fender S (2003) Molecular aspects of XY body formation. Cytogenet Genome Res 103:245–255

    Article  PubMed  CAS  Google Scholar 

  • Hughes-Schrader S, Schrader F (1961) The kinetochore of the Hemiptera. Chromosoma 12:327–350

    Article  PubMed  CAS  Google Scholar 

  • Keegan KS, Holtzman DA, Plug AW, Christenson ER, Brainerd EE, Flaggs G, Bentley NJ, Taylor EM, Meyn MS, Moss SB, Carr AM, Ashley T, Hoekstra MF (1996) The Atr and Atm protein kinases associate with different sites along meiotically pairing chromosomes. Genes Dev 10:2423–2437

    Article  PubMed  CAS  Google Scholar 

  • Koller PC, Darlington CD (1934) The genetical and mechanical properties of the sex chromosomes. I. Rattus norvergicus, O. J Genet 29:159–173

    Google Scholar 

  • Lahn BT, Page DC (1999) Four evolutionary strata on the human X chromosome. Science 286:964–967

    Article  PubMed  CAS  Google Scholar 

  • Lammers JHM, Offenberg HH, van Aalderen M, Vink ACG, Dietrich AJJ, Heyting C (1994) The gene encoding a major component of the lateral elements of synaptonemal complexes of the rat is related to X-linked lymphocyte-regulated genes. Mol Cell Biol 14:1137–1146

    PubMed  CAS  Google Scholar 

  • Lee J, Iwai T, Yokota T, Yamashita M (2003) Temporally and spatially selective loss of Rec8 protein from meiotic chromosomes during mammalian meiosis. J Cell Sci 116:2781–2790

    Article  PubMed  CAS  Google Scholar 

  • McKee BD, Handel MA (1993) Sex chromosomes, recombination and chromatin conformation. Chromosoma 102:71–80

    Article  PubMed  CAS  Google Scholar 

  • Meuwissen RLJ, Offenberg HH, Dietrich AJJ, Riesewijk A, van Iersen M, Heyting C (1992) A coiled-coil related protein specific of the synapsed regions of the meiotic prophase chromosomes. EMBO J 11:5091–5100

    PubMed  CAS  Google Scholar 

  • Moens PB (1969) The fine structure of meiotic chromosome polarization and pairing in Locusta migratoria spermatocytes. Chromosoma 28:1–25

    Article  PubMed  CAS  Google Scholar 

  • Moens PB, Earnshaw WC (1989) Anti-topoisomerase II recognizes meiotic chromosome cores. Chromosoma 98:317–322

    Article  PubMed  CAS  Google Scholar 

  • Moens PB, Spyropoulos B (1995) Immunocytology of chiasmata and chromosomal disjunction at mouse meiosis. Chromosoma 104:175–182

    Article  PubMed  CAS  Google Scholar 

  • Moens PB, Heyting C, Dietrich AJ, van Raamsdonk W, Chen Q (1987) Synaptonemal complex antigen location and conservation. J Cell Biol 105:93–103

    Article  PubMed  CAS  Google Scholar 

  • Moens PB, Tarsounas M, Morita T, Habu T, Rottinghaus ST, Freire R, Jackson SP, Barlow C, Wynshaw-Boris A (1999) The association of ATR protein with mouse meiotic chromosome cores. Chromosoma 108:95–102

    Article  PubMed  CAS  Google Scholar 

  • Molina J, Martinez-Flores I, Templado C, Garcia M, Egozcue J (1998) The synaptic process in Locusta migratoria spermatocytes by synaptonemal complex analysis. Histol Histopathol 13:949–954

    PubMed  CAS  Google Scholar 

  • Moses MJ (1956) Chromosomal structures in crayfish spermatocytes. J Biophys Biochem Cytol 2:215–217

    Article  PubMed  CAS  Google Scholar 

  • Offenberg HH, Schalk JAC, Meuwissen RLJ, van Aalderen M, Kester HA, Dietrich AJJ, Heyting C (1998) SCP2: a major protein component of the axial elements of synaptonemal complexes of the rat. Nucleic Acids Res 26:2572–2579

    Article  PubMed  CAS  Google Scholar 

  • Ohno S (1967) Sex chromosomes and sex linked genes. Springer, Berlin Heidelberg New York

    Google Scholar 

  • Olson LW, Eden U, Egel-Mitani M, Egel R (1978) Asynaptic meiosis in fission yeast? Hereditas 89:189–199

    Article  Google Scholar 

  • Page J, Berríos S, Rufas JS, Parra MT, Suja JA, Heyting C, Fernandez-Donoso R (2003) The pairing of X and Y chromosomes during meiotic prophase in the marsupial species Thylamys elegans is maintained by a dense plate developed from their axial elements. J Cell Sci 116:551–560

    Article  PubMed  CAS  Google Scholar 

  • Page J, Berríos S, Parra MT, Viera A, Suja JA, Prieto I, Barbero JL, Rufas JS, Fernandez-Donoso R (2005) The program of sex chromosome pairing in meiosis is highly conserved across marsupial species: implications for sex chromosome evolution. Genetics 170:793–799

    Article  PubMed  CAS  Google Scholar 

  • Page SL, Hawley RS (2004) The genetics and molecular biology of the synaptonemal complex. Annu Rev Cell Dev Biol 20:525–558

    Article  PubMed  CAS  Google Scholar 

  • Parra MT, Viera A, Gomez R, Page J, Benavente R, Santos JL, Rufas JS, Suja JA (2004) Involvement of the cohesin Rad21 and SCP3 in monopolar attachment of sister kinetochores during mouse meiosis I. J Cell Sci 117:1221–1234

    Article  PubMed  CAS  Google Scholar 

  • Paulson JR, Laemmli UK (1977) The structure of histone depleted chromosomes. Cell 12:817–828

    Article  PubMed  CAS  Google Scholar 

  • Pelttari J, Hoja M-R, Yuan L, Liu J-G, Brundell E, Moens P, Santucci-Darmanin S, Jessberger R, Barbero JL, Heyting C, Höög C (2001) A meiotic chromosomal core consisting of cohesin complex proteins recruits DNA recombination proteins and promotes synapsis in the absence of an axial element in mammalian meiotic cells. Mol Cell Biol 21:5667–5677

    Article  PubMed  CAS  Google Scholar 

  • Pigozzi MI, Solari AJ (2003) Differential immunolocalization of a putative Rec8p in meiotic autosomes and sex chromosomes of triatomine bugs. Chromosoma 112:38–47

    Article  PubMed  CAS  Google Scholar 

  • Prieto I, Suja JA, Pezzi N, Kremer L, Martinez-A C, Rufas JS, Barbero JL (2001) Mammalian STAG3 is a cohesin specific to sister chromatid arms in meiosis I. Nat Cell Biol 3:761–766

    Article  PubMed  CAS  Google Scholar 

  • Prieto I, Pezzi N, Buesa JM, Kremer L, Barthelemy I, Carreiro C, Roncal F, Martinez A, Gomez L, Fernandez R, Martinez-A C, Barbero JL (2002) STAG2 and Rad21 mammalian mitotic cohesins are implicated in meiosis. EMBO Rep 3:543–550

    Article  PubMed  CAS  Google Scholar 

  • Prieto I, Tease C, Pezzi N, Buesa JM, Ortega S, Kremer L, Martinez A, Martinez-A C, Hulten MA, Barbero JL (2004) Cohesin component dynamics during meiotic prophase I in mammalian oocytes. Chromosome Res 12:197–213

    Article  PubMed  CAS  Google Scholar 

  • Rasmussen SW (1973) Ultrastructural studies of spermatogenesis in Drosophila melanogaster Meigen. Z Zellforsch Mikrosk Anat 140:125–144

    Article  PubMed  CAS  Google Scholar 

  • Rasmussen SW (1977) The transformation of the Synaptonemal Complex into the ‘elimination chromatin’ in Bombyx mori oocytes. Chromosoma 60:205–221

    Article  PubMed  CAS  Google Scholar 

  • Revenkova E, Eijpe M, Heyting C, Gross B, Jessberger R (2001) Novel meiosis-specific isoform of mammalian SMC1. Mol Cell Biol 21:6984–6998

    Article  PubMed  CAS  Google Scholar 

  • Rice WR (1996) Evolution of the Y sex chromosome in animals. Bioscience 46:331–343

    Article  Google Scholar 

  • Roche L, Seluja G, Wettstein R (1986) The meiotic behaviour of the XY pair in Lutreolina crassicaudata (Marsupialia: Didelphoidea). Genetica 71:213–224

    Article  Google Scholar 

  • Rufas JS, Giménez-Martín G (1986) Ultraestructure of the kinetochore in Graphosoma italicum (Hemiptera: Heteroptera). Protoplasma 132:142–148

    Article  Google Scholar 

  • Rufas JS, Santos JL, Diez M, Suja JA (1992) Meiotic chromosome structure: relationship between the synaptonemal complex and the chromatid cores. Genome 35:1054–1061

    Google Scholar 

  • Saitoh N, Goldberg IG, Wood ER, Earnshaw WC (1994) ScII: an abundant chromosome scaffold protein is a member of a family of putative ATPases with an unusual predicted tertiary structure. J Cell Biol 127:303–318

    Article  PubMed  CAS  Google Scholar 

  • Schrader F (1939) The structure of the kinetochore at meiosis. Chromosoma 1:230–237

    Article  Google Scholar 

  • Scully R, Chen J, Plug A, Xiao Y, Weaver D, Feunteun J, Ashley T, Livingston DM (1997) Association of BRCA1 with Rad51 in mitotic and meiotic cells. Cell 88:265–275

    Article  PubMed  CAS  Google Scholar 

  • Seluja G, Roche L, Solari AJ (1987) Male meiotic prophase in Didelphis albiventris. J Hered 78:218–222

    Google Scholar 

  • Sharp P (1982) Sex chromosome pairing during male meiosis in marsupials. Chromosoma 86:27–47

    Article  PubMed  CAS  Google Scholar 

  • Smith A, Benavente R (1992) Meiosis-specific protein selectively associated with sex chromosomes of rat pachytene spermatocytes. Proc Natl Acad Sci USA 89:6938–6942

    Article  PubMed  CAS  Google Scholar 

  • Solari AJ (1969) The evolution of the ultrastructure of the sex chromosomes (sex vesicle) during the meiotic prophase in mouse spermatocytes. J Ultrastruct Res 27:289–305

    Article  PubMed  CAS  Google Scholar 

  • Solari AJ (1970a) The spatial relationship of the X and Y chromosomes during meiotic prophase in mouse spermatocytes. Chromosoma 29:217–236

    Article  PubMed  CAS  Google Scholar 

  • Solari AJ (1970b) The behaviour of chromosomal axes during diplotene in mouse spermatocytes. Chromosoma 31:217–230

    Article  PubMed  CAS  Google Scholar 

  • Solari AJ (1974) The behavior of the XY pair in mammals. Int Rev Cytol 38:273–317

    PubMed  CAS  Google Scholar 

  • Solari AJ (1979) Autosomal synaptonemal complexes and sex chromosomes without axes in Triatoma infestans (Reduviidae; Hemiptera). Chromosoma 72:225–240

    Article  Google Scholar 

  • Solari AJ (1993) Sex chromosomes and sex determination in vertebrates. CRC, Boca Raton

    Google Scholar 

  • Solari AJ, Bianchi NO (1975) The synaptic behaviour of the X and Y chromosomes in the marsupial Monodelphis dimidiata. Chromosoma 52:11–25

    Article  PubMed  CAS  Google Scholar 

  • Solari AJ, Ashley T (1977) Ultrastructure and behavior of the achiasmatic, telosynaptic XY pair of the sand rat (Psammomys obesus). Chromosoma 62:319–336

    Article  PubMed  CAS  Google Scholar 

  • Solari AJ, Counce SJ (1977) Synaptonemal complex karyotyping in Melanoplus differentialis. J Cell Sci 26:229–250

    PubMed  CAS  Google Scholar 

  • Suja JA, del Cerro AL, Page J, Rufas JS, Santos JL (2000) Meiotic sister chromatid cohesion in holocentric sex chromosomes of three heteropteran species is maintained in absence of axial elements. Chromosoma 109:35–43

    Article  PubMed  CAS  Google Scholar 

  • Tres LL (1977) Extensive pairing of the XY bivalent in mouse spermatocytes as visualized by whole-mount electron microscopy. J Cell Sci 25:1–15

    PubMed  CAS  Google Scholar 

  • Turner JM, Aprelikova O, Xu X, Wang R, Kim S, Chandramouli GV, Barrett JC, Burgoyne PS, Deng CX (2004) BRCA1, histone H2AX phosphorylation, and male meiotic sex chromosome inactivation. Curr Biol 14:2135–2142

    Article  PubMed  CAS  Google Scholar 

  • Turner JM, Mahadevaiah SK, Fernandez-Capetillo O, Nussenzweig A, Xu X, Deng CX, Burgoyne PS (2005) Silencing of unsynapsed meiotic chromosomes in the mouse. Nat Genet 37:41–47

    PubMed  CAS  Google Scholar 

  • Ueshima N (1979) Animal cytogenetics. Insecta 6. Hemiptera: Heteroptera. Borntraeger, Berlin

    Google Scholar 

  • Viera A, Calvente A, Page J, Parra MT, Gomez R, Suja JA, Rufas JS, Santos JL (2004a) X and B chromosomes display similar meiotic characteristics in male grasshoppers. Cytogenet Genome Res 106:302–308

    Article  PubMed  CAS  Google Scholar 

  • Viera A, Santos JL, Page J, Parra MT, Calvente A, Cifuentes M, Gomez R, Lira R, Suja JA, Rufas JS (2004b) DNA double-strand breaks, recombination and synapsis: the timing of meiosis differs in grasshoppers and flies. EMBO Rep 5:385–391

    Article  PubMed  CAS  Google Scholar 

  • von Wettstein D, Rasmussen SW, Holm PB (1984) The synaptonemal complex in genetic segregation. Annu Rev Genet 18:331–413

    Google Scholar 

  • Wolf KW (1994) How meiotic cells deal with non-exchange chromosomes. Bioessays 16:107–114

    Article  PubMed  CAS  Google Scholar 

  • Wolf KW, Baumgart K, Winking H (1988) Meiotic association and segregation of the giant sex chromosomes in male field vole (Microtus agrestis). Chromosoma 97:124–133

    Article  Google Scholar 

  • Xu H, Beasley M, Verschoor S, Inselman A, Handel MA, McKay MJ (2004) A new role for the mitotic RAD21/SCC1 cohesin in meiotic chromosome cohesion and segregation in the mouse. EMBO Rep 5:378–384

    Article  PubMed  CAS  Google Scholar 

Download references

Acknowledgements

We are indebt to Dr. Carlos García de la Vega for his helpful comments on the manuscript, and to Dr. Christa Heyting (Wageningen, The Netherlands) and Dr. José Luis Barbero (Madrid, Spain) for providing antibodies. This work was supported by grants BMC2002-00043 and BFU2005-05668-C03-01 from Ministerio de Educación y Ciencia (Spain), grant 1001160016 from Universidad Autónoma de Madrid (Spain), FONDECYT grants 2000008, 1040910, and 7040174 (Chile), and a grant from Centro de Estudios de América Latina-BSCH (Spain). RdlF received support from FGUAM and Olympus Optical España S.A.

Author information

Authors and Affiliations

  1. Departamento de Biología, Edificio de Ciencias Biológicas, Universidad Autónoma de Madrid, Cantoblanco, Madrid, 28049, Spain

    Jesús Page, Roberto de la Fuente, Rocío Gómez, Adela Calvente, Alberto Viera, María Teresa Parra, José Ángel Suja & Julio S. Rufas

  2. Departamento de Genética, Facultad de Biología, Universidad Complutense, Madrid, Spain

    Juan Luis Santos

  3. Programa de Genética Humana, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile

    Soledad Berríos & Raúl Fernández-Donoso

Authors
  1. Jesús Page
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Roberto de la Fuente
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Rocío Gómez
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Adela Calvente
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Alberto Viera
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. María Teresa Parra
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Juan Luis Santos
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Soledad Berríos
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Raúl Fernández-Donoso
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. José Ángel Suja
    View author publications

    You can also search for this author in PubMed Google Scholar

  11. Julio S. Rufas
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Jesús Page.

Additional information

Communicated by R. Benavente

The synaptonemal complex—50 years

Electronic supplementary material

3-D reconstruction of a Locusta migratoria pachytene spermatocyte immunolabelled against the cohesin subunit SMC3 (green). At the right movie the chromatin is counterstained with DAPI (blue). The position of the X chromosome is indicated by an X. Notice the presence of a single and continuous cohesin axis inside the chromatin of the X chromosome, that is thinner than that exhibited by the synapsed autosomal bivalents. For the correct visualization of the movie select the boucle option in the video player (MOV 917 kb)

3D reconstruction throughout two spermatocyte nuclei of the hemipteran species Graphosoma italicum. In both spermatocytes the chromatin is stained with DAPI (blue) and the sex chromosomes are located at the nuclear periphery (XY). In the left reconstruction the SYCP3 protein of the synaptonemal complex is stained (green), the absence of signalling inside the sex chromatin being evident. Note that the position of the autosomal synaptonemal complexes appears in focal plains that are different from those occupied by the sex chromosomes. On the contrary, in the right reconstruction, in which the SMC3 subunit of the cohesin complex is detected (green), conspicuous threads are located inside the sex chromatin. For the correct visualization of the movie select the boucle option in the video player (MOV 720 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Page, J., de la Fuente, R., Gómez, R. et al. Sex chromosomes, synapsis, and cohesins: a complex affair. Chromosoma 115, 250–259 (2006). https://doi.org/10.1007/s00412-006-0059-3

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00412-006-0059-3

Keywords

Search

Navigation