Gene Symbol: Psc
Description: Posterior sex combs
Alias: 49Ea, CG3886, D-Bmi, Dmel\CG3886, PSC, Psc1, Su(z)2-C, dPSC, l(2)49Ea, l(2)Psc, l(2)vr14, psc, vr14, posterior sex combs, CG3886-PA, CG3886-PB, CG3886-PC, Psc-PA, Psc-PB, Psc-PC, posterior sex comb, posterior-sex-combs
Species: fruit fly
Products:     Psc

Top Publications

  1. Gaytán de Ayala Alonso A, Gutierrez L, Fritsch C, Papp B, Beuchle D, Muller J. A genetic screen identifies novel polycomb group genes in Drosophila. Genetics. 2007;176:2099-108 pubmed
    ..The results of the mutant screen reported here suggest that the majority of nonredundant Drosophila genes with strong classic PcG phenotypes have been identified. ..
  2. van Lohuizen M, Frasch M, Wientjens E, Berns A. Sequence similarity between the mammalian bmi-1 proto-oncogene and the Drosophila regulatory genes Psc and Su(z)2. Nature. 1991;353:353-5 pubmed
    ..Chromosomal localization and sequence comparison reveal that D-bmi is identical to Posterior Sex Combs (Psc) and indicate that the conserved domains between mouse bmi and Psc are also conserved within ..
  3. Paro R. Imprinting a determined state into the chromatin of Drosophila. Trends Genet. 1990;6:416-21 pubmed
  4. Kennison J. The Polycomb and trithorax group proteins of Drosophila: trans-regulators of homeotic gene function. Annu Rev Genet. 1995;29:289-303 pubmed
    ..The ZESTE protein may help to activate transcription by bringing distant cis-regulatory elements closer to promoter-bound proteins. ..
  5. Li X, Han Y, Xi R. Polycomb group genes Psc and Su(z)2 restrict follicle stem cell self-renewal and extrusion by controlling canonical and noncanonical Wnt signaling. Genes Dev. 2010;24:933-46 pubmed publisher
    ..We show that Posterior sex combs (Psc), which encodes a core Polycomb-repressive complex 1 (PRC1) component, functions redundantly with a ..
  6. Buchenau P, Hodgson J, Strutt H, Arndt Jovin D. The distribution of polycomb-group proteins during cell division and development in Drosophila embryos: impact on models for silencing. J Cell Biol. 1998;141:469-81 pubmed
    ..three-dimensional distribution of three polycomb-group (PcG) proteins-polycomb, polyhomeotic and posterior sex combs-in fixed whole-mount Drosophila embryos was analyzed by multicolor confocal fluorescence microscopy...
  7. Wu C, Howe M. A genetic analysis of the Suppressor 2 of zeste complex of Drosophila melanogaster. Genetics. 1995;140:139-81 pubmed
    ..The Su(z)2-C consists of at least three subregions called Psc (Posterior sex combs), Su(z)2 and Su(z)2D (Distal)...
  8. Chinwalla V, Jane E, Harte P. The Drosophila trithorax protein binds to specific chromosomal sites and is co-localized with Polycomb at many sites. EMBO J. 1995;14:2056-65 pubmed
    ..Co-localization with Polycomb also suggests that interactions between these activators and repressors of the homeotic genes may be a significant feature of their mode of action. ..
  9. Francis N, Follmer N, Simon M, Aghia G, Butler J. Polycomb proteins remain bound to chromatin and DNA during DNA replication in vitro. Cell. 2009;137:110-22 pubmed publisher
    ..Retention of Polycomb proteins through DNA replication may contribute to maintenance of transcriptional silencing through cell division. ..

More Information


  1. Randsholt N, Maschat F, Santamaria P. polyhomeotic controls engrailed expression and the hedgehog signaling pathway in imaginal discs. Mech Dev. 2000;95:89-99 pubmed
    ..We suggest that PcG targets are not exclusively regulated by an on/off mechanism, but that the PcG also exerts negative transcriptional control on active genes. ..
  2. Gutierrez L, Oktaba K, Scheuermann J, Gambetta M, Ly Hartig N, Muller J. The role of the histone H2A ubiquitinase Sce in Polycomb repression. Development. 2012;139:117-27 pubmed publisher
    ..Drosophila PcG proteins Sex combs extra (Sce; dRing) and Posterior sex combs (Psc) are core subunits of PRC1-type complexes...
  3. Bunker C, Kingston R. Transcriptional repression by Drosophila and mammalian Polycomb group proteins in transfected mammalian cells. Mol Cell Biol. 1994;14:1721-32 pubmed
    ..The murine oncogene bmi-1 has significant homology to the Pc-G gene Posterior sex combs (Psc) and a highly related gene, Suppressor two of zeste [Su(z)2]...
  4. Kassis J. Unusual properties of regulatory DNA from the Drosophila engrailed gene: three "pairing-sensitive" sites within a 1.6-kb region. Genetics. 1994;136:1025-38 pubmed
    ..I propose that engrailed PS sites normally act to promote interactions between distantly located engrailed regulatory sites and the engrailed promoter. ..
  5. Oktaba K, Gutierrez L, Gagneur J, Girardot C, Sengupta A, Furlong E, et al. Dynamic regulation by polycomb group protein complexes controls pattern formation and the cell cycle in Drosophila. Dev Cell. 2008;15:877-89 pubmed publisher
    ..Analysis of cell cycle regulators indicates that the PcG system also dynamically modulates the expression levels of certain genes, providing a possible explanation for the tumor phenotype of PcG mutants. ..
  6. Breiling A, Turner B, Bianchi M, Orlando V. General transcription factors bind promoters repressed by Polycomb group proteins. Nature. 2001;412:651-5 pubmed
    ..We further show that PcG proteins interact in vitro with GTFs. We suggest that PcG complexes maintain silencing by inhibiting GTF-mediated activation of transcription. ..
  7. Papp B, Muller J. Histone trimethylation and the maintenance of transcriptional ON and OFF states by trxG and PcG proteins. Genes Dev. 2006;20:2041-54 pubmed
  8. Maeda R, Karch F. The ABC of the BX-C: the bithorax complex explained. Development. 2006;133:1413-22 pubmed
    ..This primer attempts to distill and explain our current knowledge about this classic, complex locus. ..
  9. Lo S, Ahuja N, Francis N. Polycomb group protein Suppressor 2 of zeste is a functional homolog of Posterior Sex Combs. Mol Cell Biol. 2009;29:515-25 pubmed publisher
    The Drosophila melanogaster Polycomb group protein Posterior Sex Combs is a component of Polycomb repressive complex 1 and is central to Polycomb group-mediated silencing...
  10. Kyba M, Brock H. The Drosophila polycomb group protein Psc contacts ph and Pc through specific conserved domains. Mol Cell Biol. 1998;18:2712-20 pubmed
    ..We show that ph and Psc coprecipitate with Pc from nuclear extracts...
  11. Classen A, Bunker B, Harvey K, Vaccari T, Bilder D. A tumor suppressor activity of Drosophila Polycomb genes mediated by JAK-STAT signaling. Nat Genet. 2009;41:1150-5 pubmed publisher
    ..These findings show that PcG proteins can restrict growth directly by silencing mitogenic signaling pathways, shedding light on an epigenetic mechanism underlying tumor suppression. ..
  12. Orlando V, Paro R. Chromatin multiprotein complexes involved in the maintenance of transcription patterns. Curr Opin Genet Dev. 1995;5:174-9 pubmed
    ..The role of the trithorax-group factors is to counteract these repressed chromatin domains and thus to render the genes accessible to activating factors. ..
  13. Rastelli L, Chan C, Pirrotta V. Related chromosome binding sites for zeste, suppressors of zeste and Polycomb group proteins in Drosophila and their dependence on Enhancer of zeste function. EMBO J. 1993;12:1513-22 pubmed
    ..Some of these genes, e.g. Psc, Su(z)2 and E(z), are also modifiers of the zeste-white interaction...
  14. Kavi H, Fernandez H, Xie W, Birchler J. Polycomb, pairing and PIWI--RNA silencing and nuclear interactions. Trends Biochem Sci. 2006;31:485-7 pubmed
    ..These Pc-associated sequences are involved with the control of the proper expression of developmental HOX genes. ..
  15. Narbonne K, Besse F, Brissard Zahraoui J, Pret A, Busson D. polyhomeotic is required for somatic cell proliferation and differentiation during ovarian follicle formation in Drosophila. Development. 2004;131:1389-400 pubmed
    ..Our results provide a new model system, the Drosophila ovary, in which the function of Pc-G genes, distinct from that of control of homeotic gene expression, can be explored. ..
  16. Henikoff S, Henikoff J, Sakai A, Loeb G, Ahmad K. Genome-wide profiling of salt fractions maps physical properties of chromatin. Genome Res. 2009;19:460-9 pubmed publisher
  17. Paro R. Mechanisms of heritable gene repression during development of Drosophila. Curr Opin Cell Biol. 1993;5:999-1005 pubmed
    ..Recent experiments demonstrate that, in particular, the heritable inactivation of regulatory genes relies on stable changes in the higher-order constitution of chromatin. ..
  18. Strübbe G, Popp C, Schmidt A, Pauli A, Ringrose L, Beisel C, et al. Polycomb purification by in vivo biotinylation tagging reveals cohesin and Trithorax group proteins as interaction partners. Proc Natl Acad Sci U S A. 2011;108:5572-7 pubmed publisher
    ..Furthermore, our analysis revealed an association of PcG protein complexes with the cohesin complex and showed that Polycomb-dependent silencing of a transgenic reporter depends on cohesin function. ..
  19. Poux S, Melfi R, Pirrotta V. Establishment of Polycomb silencing requires a transient interaction between PC and ESC. Genes Dev. 2001;15:2509-14 pubmed
    ..extracts, we find PC transiently associated with ESC in a complex that includes EZ, PHO, PH, GAGA, and RPD3 but not PSC. In older embryos, PC is found in a complex including PH, PSC, GAGA, and RPD3, whereas ESC is in a separate complex ..
  20. Simon J, Chiang A, Bender W. Ten different Polycomb group genes are required for spatial control of the abdA and AbdB homeotic products. Development. 1992;114:493-505 pubmed, Sex comb on midleg (Scm), Polycomb-like (Pcl), Sex comb extra (Sce), Additional sex combs (Asx), Posterior sex combs (Psc) and pleiohomeotic (pho) were examined...
  21. Beisel C, Buness A, Roustan Espinosa I, Koch B, Schmitt S, Haas S, et al. Comparing active and repressed expression states of genes controlled by the Polycomb/Trithorax group proteins. Proc Natl Acad Sci U S A. 2007;104:16615-20 pubmed
    ..Besides its presumptive function in recruiting PcG complexes to their site of action, our results now uncover that Pho plays an additional role in the repression of already induced genes. ..
  22. Goodliffe J, Wieschaus E, Cole M. Polycomb mediates Myc autorepression and its transcriptional control of many loci in Drosophila. Genes Dev. 2005;19:2941-6 pubmed
    ..Our results suggest a novel relationship between Myc and Polycomb, wherein Myc enhances Polycomb repression in order to repress targets, and Myc suppresses Polycomb repression in order to activate targets. ..
  23. Francis N, Saurin A, Shao Z, Kingston R. Reconstitution of a functional core polycomb repressive complex. Mol Cell. 2001;8:545-56 pubmed
    ..One subunit, PSC, can also inhibit chromatin remodeling on its own...
  24. Emmons R, Genetti H, Filandrinos S, Lokere J, Wu C. Molecular genetic analysis of Suppressor 2 of zeste identifies key functional domains. Genetics. 2009;182:999-1013 pubmed publisher
    The Su(z)2 complex contains Posterior sex combs (Psc) and Suppressor 2 of zeste [Su(z)2], two paralogous genes that likely arose by gene duplication...
  25. Irminger Finger I, Nothiger R. The Drosophila melanogaster gene lethal(3)73Ah encodes a ring finger protein homologous to the oncoproteins MEL-18 and BMI-1. Gene. 1995;163:203-8 pubmed
    ..mel-18 and bmi-1, and to the zinc-finger-containing N-terminal region of the Dm proteins encoded by the Posterior sex combs and Suppressor two of zeste genes...
  26. Schwartz Y, Kahn T, Nix D, Li X, Bourgon R, Biggin M, et al. Genome-wide analysis of Polycomb targets in Drosophila melanogaster. Nat Genet. 2006;38:700-5 pubmed
    ..Here, we determined the distribution of the PcG proteins PC, E(Z) and PSC and of trimethylation of histone H3 Lys27 (me3K27) in the D. melanogaster genome...
  27. Strutt H, Paro R. The polycomb group protein complex of Drosophila melanogaster has different compositions at different target genes. Mol Cell Biol. 1997;17:6773-83 pubmed
    ..In addition, Posterior Sex Combs protein coimmunoprecipitates Polycomb and Polyhomeotic, indicating that they are members of a common ..
  28. Mito Y, Henikoff J, Henikoff S. Histone replacement marks the boundaries of cis-regulatory domains. Science. 2007;315:1408-11 pubmed
    ..Our results suggest the existence of a continuous process that disrupts nucleosomes and maintains accessibility of cis-regulatory elements. ..
  29. King I, Emmons R, Francis N, Wild B, Muller J, Kingston R, et al. Analysis of a polycomb group protein defines regions that link repressive activity on nucleosomal templates to in vivo function. Mol Cell Biol. 2005;25:6578-91 pubmed
    ..Genetic and biochemical studies suggest the product of the Posterior sex combs (Psc) gene plays a central role in both PcG-mediated gene repression in vivo and PRC1 activity in vitro...
  30. Soto M, Chou T, Bender W. Comparison of germline mosaics of genes in the Polycomb group of Drosophila melanogaster. Genetics. 1995;140:231-43 pubmed
    ..Five members of the PcG group are compared here: Enhancer of Polycomb [E(Pc)], Additional sex combs (Asx), Posterior sex combs (Psc), Suppressor of zeste 2 [Su (z) 2] and Polycomblike (Pcl)...
  31. Brown J, Fritsch C, Mueller J, Kassis J. The Drosophila pho-like gene encodes a YY1-related DNA binding protein that is redundant with pleiohomeotic in homeotic gene silencing. Development. 2003;130:285-94 pubmed
    ..We examined the distribution of five PcG proteins on polytene chromosomes from pho-like, pho double mutants. Pc, Psc, Scm, E(z) and Ph remain bound to polytene chromosomes at most sites in the absence of Pho and Pho-like...
  32. Erhardt S, Lyko F, Ainscough J, Surani M, Paro R. Polycomb-group proteins are involved in silencing processes caused by a transgenic element from the murine imprinted H19/Igf2 region in Drosophila. Dev Genes Evol. 2003;213:336-44 pubmed
    ..In addition, two members of the conserved Polycomb group, Enhancer of zeste and Posterior sex combs, were needed for repression. Polycomb group proteins are essential for gene silencing during development...
  33. Bantignies F, Grimaud C, Lavrov S, Gabut M, Cavalli G. Inheritance of Polycomb-dependent chromosomal interactions in Drosophila. Genes Dev. 2003;17:2406-20 pubmed
    ..This suggests that transmission of nuclear architecture through cell division might contribute to inheritance of chromatin states in eukaryotes. ..
  34. Lagarou A, Mohd Sarip A, Moshkin Y, Chalkley G, Bezstarosti K, Demmers J, et al. dKDM2 couples histone H2A ubiquitylation to histone H3 demethylation during Polycomb group silencing. Genes Dev. 2008;22:2799-810 pubmed publisher
    ..factors (dRAF), a novel Polycomb group (PcG) silencing complex harboring the histone H2A ubiquitin ligase dRING, PSC and the F-box protein, and demethylase dKDM2...
  35. Mohd Sarip A, van der Knaap J, Wyman C, Kanaar R, Schedl P, Verrijzer C. Architecture of a polycomb nucleoprotein complex. Mol Cell. 2006;24:91-100 pubmed
    ..Indeed, chromatin immunoprecipitations (ChIPs) and nuclease mapping demonstrated that PREs are nucleosome depleted in vivo. We discuss the implications of these findings for models explaining PRE function. ..
  36. Shao Z, Raible F, Mollaaghababa R, Guyon J, Wu C, Bender W, et al. Stabilization of chromatin structure by PRC1, a Polycomb complex. Cell. 1999;98:37-46 pubmed
    ..complex, termed PRC1 (Polycomb repressive complex 1), that contains the products of the PcG genes Polycomb, Posterior sex combs, polyhomeotic, Sex combs on midleg, and several other proteins...
  37. King I, Francis N, Kingston R. Native and recombinant polycomb group complexes establish a selective block to template accessibility to repress transcription in vitro. Mol Cell Biol. 2002;22:7919-28 pubmed
    ..We find that assembly of the template into nucleosomes enhances repression by PRC1 and PCC. The subunit Psc is able to inhibit transcription on its own...
  38. Cavalli G, Paro R. Epigenetic inheritance of active chromatin after removal of the main transactivator. Science. 1999;286:955-8 pubmed
    ..This feature may allow epigenetic maintenance of active states of developmental genes after decay of their early embryonic regulators. ..
  39. Busturia A, Lloyd A, Bejarano F, Zavortink M, Xin H, Sakonju S. The MCP silencer of the Drosophila Abd-B gene requires both Pleiohomeotic and GAGA factor for the maintenance of repression. Development. 2001;128:2163-73 pubmed
    ..However, when both PHO and GAF binding sites are present, they achieve strong silencing. We present a model in which robust silencing is achieved by sequential and facilitated binding of PHO and GAF. ..
  40. Brunk B, Martin E, Adler P. Drosophila genes Posterior Sex Combs and Suppressor two of zeste encode proteins with homology to the murine bmi-1 oncogene. Nature. 1991;353:351-3 pubmed
    ..We report the predicted protein sequence of the Pc-G gene Posterior Sex Combs (Psc), and of the neighbouring and related gene Suppressor two of zeste (Su(z)2)...
  41. Mohd Sarip A, Lagarou A, Doyen C, van der Knaap J, Aslan U, Bezstarosti K, et al. Transcription-independent function of Polycomb group protein PSC in cell cycle control. Science. 2012;336:744-7 pubmed publisher
    ..We describe a transcription-independent function for PcG protein Posterior sex combs (PSC) in regulating the destruction of cyclin B (CYC-B)...
  42. Kahn T, Schwartz Y, Dellino G, Pirrotta V. Polycomb complexes and the propagation of the methylation mark at the Drosophila ubx gene. J Biol Chem. 2006;281:29064-75 pubmed
    ..Both the spread of methylation from the Polycomb response elements, and the silencing effect can be blocked by the gypsy insulator. ..
  43. Czermin B, Melfi R, McCabe D, Seitz V, Imhof A, Pirrotta V. Drosophila enhancer of Zeste/ESC complexes have a histone H3 methyltransferase activity that marks chromosomal Polycomb sites. Cell. 2002;111:185-96 pubmed
    ..Histone H3 methylated in vitro by the E(Z)/ESC complex binds specifically to Polycomb protein. ..
  44. Lo S, Follmer N, Lengsfeld B, Madamba E, Seong S, Grau D, et al. A bridging model for persistence of a polycomb group protein complex through DNA replication in vitro. Mol Cell. 2012;46:784-96 pubmed publisher
    ..Here we investigate the mechanism of persistence. We find that a single PRC1 subunit, Posterior sex combs (PSC), can reconstitute persistence through DNA replication...
  45. Pirrotta V. Chromatin complexes regulating gene expression in Drosophila. Curr Opin Genet Dev. 1995;5:466-72 pubmed
    ..How they persist through cell proliferation and how they silence gene activity are still open issues. ..
  46. Simon J. Locking in stable states of gene expression: transcriptional control during Drosophila development. Curr Opin Cell Biol. 1995;7:376-85 pubmed
  47. Martin E, Adler P. The Polycomb group gene Posterior Sex Combs encodes a chromosomal protein. Development. 1993;117:641-55 pubmed
    The Posterior Sex Combs (Psc) gene of Drosophila has been studied at the molecular level both because it is a Polycomb group (Pc-G) gene and hence required for the maintenance of segmental determination, and because it is the Drosophila ..
  48. Enderle D, Beisel C, Stadler M, Gerstung M, Athri P, Paro R. Polycomb preferentially targets stalled promoters of coding and noncoding transcripts. Genome Res. 2011;21:216-26 pubmed publisher
    ..Interestingly, this set includes previously unknown promoters for primary transcripts of microRNA genes, thereby expanding the scope of Polycomb control to noncoding RNAs essential for development, apoptosis, and growth. ..
  49. Brown J, Kassis J. Spps, a Drosophila Sp1/KLF family member, binds to PREs and is required for PRE activity late in development. Development. 2010;137:2597-602 pubmed publisher
    ..PREs, and that Spps binds to polytene chromosomes in a pattern virtually identical to that of the PcG protein, Psc. A deletion of the Spps gene causes lethality late in development and a loss in pairing-sensitive silencing, an ..
  50. Schwartz Y, Kahn T, Stenberg P, Ohno K, Bourgon R, Pirrotta V. Alternative epigenetic chromatin states of polycomb target genes. PLoS Genet. 2010;6:e1000805 pubmed publisher
    ..These results have important implications for Polycomb gene regulation, the "bivalent" chromatin state of embryonic stem cells, and gene expression in development. ..
  51. Beuchle D, Struhl G, Muller J. Polycomb group proteins and heritable silencing of Drosophila Hox genes. Development. 2001;128:993-1004 pubmed
    ..Some PcG proteins may be required to define and propagate this mark; others may function to repress the transcription of Hox genes that bear the mark. ..
  52. Campbell R, Sinclair D, Couling M, Brock H. Genetic interactions and dosage effects of Polycomb group genes of Drosophila. Mol Gen Genet. 1995;246:291-300 pubmed
    ..The results support the idea that Additional sex combs (Asx), Pc, Polycomblike (Pcl), Posterior sex combs (Psc), Sex combs on midleg (Scm), and Sex combs extra (Sce) have similar functions in some imaginal tissues...
  53. Deal R, Henikoff J, Henikoff S. Genome-wide kinetics of nucleosome turnover determined by metabolic labeling of histones. Science. 2010;328:1161-4 pubmed publisher
  54. Sharp E, Martin E, Adler P. Directed overexpression of suppressor 2 of zeste and Posterior Sex Combs results in bristle abnormalities in Drosophila melanogaster. Dev Biol. 1994;161:379-92 pubmed
    ..into flies Hsp70:cDNA constructs for Su(z)2 and the related and neighboring Polycomb group (Pc-G) gene Posterior Sex Combs (Psc)...
  55. Gandille P, Narbonne Reveau K, Boissonneau E, Randsholt N, Busson D, Pret A. Mutations in the polycomb group gene polyhomeotic lead to epithelial instability in both the ovary and wing imaginal disc in Drosophila. PLoS ONE. 2010;5:e13946 pubmed publisher
  56. Muller M, Hagstrom K, Gyurkovics H, Pirrotta V, Schedl P. The mcp element from the Drosophila melanogaster bithorax complex mediates long-distance regulatory interactions. Genetics. 1999;153:1333-56 pubmed
    ..Finally, this pairing element can also mediate long-distance interactions between enhancers and promoters, activating mini-white expression. ..
  57. Kharchenko P, Alekseyenko A, Schwartz Y, Minoda A, Riddle N, Ernst J, et al. Comprehensive analysis of the chromatin landscape in Drosophila melanogaster. Nature. 2011;471:480-5 pubmed publisher
    ..This systematic profiling and integrative analysis of chromatin signatures provides insights into how genomic elements are regulated, and will serve as a resource for future experimental investigations of genome structure and function. ..
  58. Cheng N, Sinclair D, Campbell R, Brock H. Interactions of polyhomeotic with Polycomb group genes of Drosophila melanogaster. Genetics. 1994;138:1151-62 pubmed
    ..We observed extragenic noncomplementation between ph503 and Pc, Psc1 and Su(z)2(1) in females, and between ph409 and Sce1, ScmD1 and E(z)1 mutations in males, suggesting that these ..
  59. Poux S, McCabe D, Pirrotta V. Recruitment of components of Polycomb Group chromatin complexes in Drosophila. Development. 2001;128:75-85 pubmed
    ..When LexA-PC, -PSC, -PH or -SU(Z)2 are targeted to a reporter gene, they recruit functional PcG-silencing complexes that recapitulate ..
  60. Lavigne M, Francis N, King I, Kingston R. Propagation of silencing; recruitment and repression of naive chromatin in trans by polycomb repressed chromatin. Mol Cell. 2004;13:415-25 pubmed
    ..A Drosophila PRC core complex (dPCC) also is able to recruit a second template. Posterior sex combs (PSC), a subunit of dPCC, inhibits chromatin remodeling and transcription efficiently but requires assembly ..
  61. Fanti L, Perrini B, Piacentini L, Berloco M, Marchetti E, Palumbo G, et al. The trithorax group and Pc group proteins are differentially involved in heterochromatin formation in Drosophila. Chromosoma. 2008;117:25-39 pubmed
    ..These results strongly suggest that trx-G proteins, along with some Pc-G proteins, play an active role in heterochromatin formation in Drosophila. ..