References

1. Felsenfeld, G.; Groudine, M. Controlling the double helix. Nature 2003, 42, 448–453.
2. Luger, K.; Dechassa, M.L.; Tremethick, D.J. New insights into nucleosome and chromatin structure: An ordered state or a disordered affair?. Nat. Rev. Mol. Cell Biol. 2012, 13, 436–447.
3. Brueckner, L.; van Arensbergen, J.; Akhtar, W.; Pagie, L.; van Steensel, B. High-throughput assessment of context-dependent effects of chromatin proteins. Epigenetics Chromatin. 2016, 9, 1–17.
4. Luger, K.; Mader, A.W.; Richmond, R.K.; Sargent, D.F.; Richmond, T.J. Crystal structure of the nucleosome resolution core particle at 2.8 A. Nature 1997, 389, 251–260.
5. Bayona-Feliu, A.; Casas-Lamesa, A.; Reina, O.; Bernués, J.; Azorín, F. Linker histone H1 prevents R-loop accumulation and genome instability in heterochromatin. Nat. Commun. 2017, 8, 1.
6. Richards, E.J.; Elgin, S.C.R. Epigenetic codes for heterochromatin formation and silencing: Rounding up the usual suspects. Cell 2002, 108, 489–500.
7. Piacentini, L.; Fanti, L.; Negri, R.; Del Vescovo, V.; Fatica, A.; Altieri, F.; Pimpinelli, S. Heterochromatin Protein 1 (HP1a) positively regulates euchromatic gene expression through RNA transcript association and interaction with hnRNPs in Drosophila. PLoS Genet. 2009, 5, 10.
8. Passarge, E. Emil Heitz and the concept of heterochromatin: Longitudinal chromosome differentiation was recognized fifty years ago. Am. J. Hum. Genet. 1979, 31, 106–115.
9. Dillon, N. Heterochromatin structure and function. Biol. Cell 2004, 96, 631–637.
10. Britten, R.J.; Kohne, D.E. Repeated sequences in DNA. Science 1968, 161, 529–540.
11. Fodor, B.D.; Shukeir, N.; Reuter, G.; Jenuwein, T. Mammalian Su (var) genes in chromatin control. Annu. Rev. Cell Dev. Biol. 2010, 26, 471–501.
12. Guthmann, M.; Burton, A.; Torres-Padilla, M. Expression and phase separation potential of heterochromatin proteins during early mouse development. EMBO Rep. 2019, 20, 1–11.
13. Nishibuchi, G.; Déjardin, J. The molecular basis of the organization of repetitive DNA-containing constitutive heterochromatin in mammals. Chromosom. Res. 2017, 25, 77–87.
14. Fanti, L.; Pimpinelli, S. HP1: A functionally multifaceted protein. Curr. Opin. Genet. Dev. 2008, 18, 169–174.
15. Pindyurin, A.V.; Ilyin, A.A.; Ivankin, A.V.; Tselebrovsky, M.V.; Nenasheva, V.V.; Mikhaleva, E.A.; Pagie, L.; van Steensel, B.; Shevelyov, Y.Y. The large fraction of heterochromatin in Drosophila neurons is bound by both B-type lamin and HP1a. Epigenetics Chromatin. 2018, 11, 1–17.
16. Riddle, N.C.; Minoda, A.; Kharchenko, P.V.; Alekseyenko, A.A.; Schwartz, Y.B.; Tolstorukov, M.Y.; Gorchakov, A.A.; Jaffe, J.D.; Kennedy, C.; Linder-Basso, D.; et al. Plasticity in patterns of histone modifications and chromosomal proteins in Drosophila heterochromatin. Genome Res. 2011, 21, 147–163.
17. Marshall, O.J.; Brand, A.H. Chromatin state changes during neural development revealed by in vivo cell-type specific profiling. Nat. Commun. 2017, 8, 1–9.
18. Grewal, S. Heterochromatin and epigenetic control of gene expression. Science 2003, 301, 798–802.
19. Wang, X.; Moazed, D. DNA sequence-dependent epigenetic inheritance of gene silencing and histone H3K9 methylation. Science 2017, 91, 88–91.
20. Riddle, N.C.; Jung, Y.L.; Gu, T.; Alekseyenko, A.A.; Asker, D.; Gui, H.; Kharchenko, P.V.; Minoda, A.; Plachetka, A.; Schwartz, Y.B.; et al. Enrichment of HP1a on drosophila chromosome 4 genes creates an alternate chromatin structure critical for regulation in this heterochromatic domain. PLoS Genet. 2012, 8, 9.
21. Muller, H.J.; Altenburg, E. The frequency of translocations produced by X-rays in Drosophila. Genetics 1930, 15, 283–311.
22. James, T.C.; Elgin, S.C. Identification of a nonhistone chromosomal protein associated with heterochromatin in Drosophila melanogaster and its gene. Mol. Cell. Biol. 1986, 6, 3862–3872.
23. Sinclair, D.A.R.; Mottus, R.C.; Grigliatti, T.A. Genes which suppress position-effect variegation in Drosophila melanogaster are clustered. MGG Mol. Gen. Genet. 1983, 191, 326–333.
24. Lorentz, A.; Ostermann, K.; Fleck, O.; Schmidt, H. Switching gene swi6, involved in repression of silent mating-type loci in fission yeast , encodes a homologue of chromatin-associated proteins from Drosophila and mammals. Gene 1994, 143, 139–143.
25. Thon, G.; Verhein-hansen, J. Four chromo-domain proteins of schizosaccharomyces pombe differentially repress transcription at various chromosomal locations. Genetics 2000, 155, 551–568.
26. Meehan, R.R.; Kao, C.F.; Pennings, S. HP1 binding to native chromatin in vitro is determined by the hinge region and not by the chromodomain. EMBO J. 2003, 22, 3164–3174.
27. Istomina, N.E.; Shushanov, S.S.; Springhetti, E.M.; Karpov, V.L.; Krasheninnikov, I.A.; Stevens, K.; Zaret, K.S.; Singh, P.B.; Grigoryev, S.A. Insulation of the chicken beta-globin chromosomal domain from a chromatin-condensing protein, MENT. Mol. Cell. Biol. 2003, 23, 6455–6468.
28. Wreggett, K.A.; Hill, F.; James, P.S.; Hutchings, A.; Butcher, G.W.; Singh, P.B. A mammalian homologue of Drosophila heterochromatin protein 1 (HP1) is a component of constitutive heterochromatin. Cytogenet. Cell Genet. 1994, 66, 99–103.
29. Cowell, I.G.; Aucott, R.; Mahadevaiah, S.K.; Burgoyne, P.S.; Huskisson, N.; Bongiorni, S.; Prantera, G.; Fanti, L.; Pimpinelli, S.; Wu, R.; et al. Heterochromatin, HP1 and methylation at lysine 9 of histone H3 in animals. Chromosoma 2002, 111, 22–36.
30. Pak, D.T.; Pflumm, M.; Chesnokov, I.; Huang, D.W.; Kellum, R.; Marr, J.; Romanowski, P.; Botchan, M.R. Association of the origin recognition complex with heterochromatin and HP1 in higher eukaryotes. Cell 1997, 91, 311–323.
31. Polioudaki, H.; Kourmouli, N.; Drosou, V.; Bakou, A.; Theodoropoulos, P.A.; Singh, P.B.; Giannakouros, T.; Georgatos, S.D. Histones H3/H4 form a tight complex with the inner nuclear membrane protein LBR and heterochromatin protein 1. EMBO Rep. 2001, 2, 920–925.
32. Raffa, G.D.; Ciapponi, L.; Cenci, G.; Gatti, M. Terminin: A protein complex that mediates epigenetic maintenance of Drosophila telomeres. Nucleus 2011, 2, 383–391.
33. van Bortle, K.; Corces, V.G. Nuclear organization and genome function. Annu. Rev. Cell Dev. Biol. 2012, 28, 163–187.
34. Beishline, K.; Vladimirova, O.; Tutton, S.; Wang, Z.; Deng, Z.; Lieberman, P.M. CTCF driven TERRA transcription facilitates completion of telomere DNA replication. Nat. Commun. 2017, 8, 1–10.
35. Lis, J.T.; Simon, J.A.; Sutton, C.A. New heat shock puffs and β-galactosidase activity resulting from transformation of Drosophila with an hsp70-lacZ hybrid gene. Cell 1983, 35, 403–410.
36. Kellum, R.; Schedl, P. A position-effect assay for boundaries of higher order chromosomal domains. Cell 1991, 64, 941–950.
37. Udvardy, A.; Maine, E.; Schedl, P. The 87A7 chromomere. Identification of novel chromatin structures flanking the heat shock locus that may define the boundaries of higher order domains. J. Mol. Biol. 1985, 185, 341–358.
38. Li, Q.; Starnatoyannopoulos, G. Hypersensitive site 5 of the human B Locus control region functions as a chromatin insulator. Blood 1994, 84, 1399–1401.
39. Filippova, G.N.; Fagerlie, S.; Klenova, E.M.; Myers, C.; Dehner, Y.; Goodwin, G.; Neiman, P.E.; Collins, S.J.; Lobanenkov, V.V. An exceptionally conserved transcriptional repressor, CTCF, employs different combinations of zinc fingers to bind diverged promoter sequences of avian and mammalian c-myc oncogenes. Mol. Cell. Biol. 1996, 16, 2802–2813.
40. Felsenfeld, G.; Bell, A.C. Methylation of a CTCF-dependent boundary controls imprinted expressionof the Igf2 gene. Nature 2000, 405, 482–485.
41. Rao, S.S.; Huntley, M.H.; Durand, N.C.; Stamenova, E.K.; Bochkov, I.D.; Robinson, J.T.; Sanborn, A.L.; Machol, I.; Omer, A.D.; Lander, E.S.; et al. A 3D map of the human genome at kilobase resolution reveals principles of chromatin looping. Cell 2014, 159, 1665–1680.
42. Dixon, J.R.; Selvaraj, S.; Yue, F.; Kim, A.; Li, Y.; Shen, Y.; Hu, M.; Liu, J.S.; Ren, B. Topological domains in mammalian genomes identified by analysis of chromatin interactions. Nature 2012, 485, 376–380.
43. Brackley, C.A.; Johnson, J.; Michieletto, D.; Morozov, A.; Nicodemi, M.; Cook, P.; Marenduzzo, D. Nonequilibrium chromosome looping via molecular slip links. Phys. Rev. Lett. 2017, 119, 1–5.
44. Maksimenko, O.; Bartkuhn, M.; Stakhov, V.; Herold, M.; Zolotarev, N.; Jox, T.; Buxa, M.K.; Kirsch, R.; Bonchuk, A.; Fedotova, A.; et al. Two new insulator proteins, Pita and ZIPIC, target CP190 to chromatin. Genome Res. 2015, 25, 89–99.
45. Van Bortle, K.; Nichols, M.H.; Li, L.; Ong, C.T.; Takenaka, N.; Qin, Z.S.; Corces, V.G. Insulator function and topological domain border strength scale with architectural protein occupancy. Genome Biol. 2014, 15, R82.
46. Yang, J.; Ramos, E.; Corces, V.G. The BEAF-32 insulator coordinates genome organization and function during the evolution of Drosophila species. Genome Res. 2012, 22, 2199–2207.
47. Roseman, R.R.; Pirrotta, V.; Geyer, P.K. The su(Hw) protein insulates expression of the drosophila melanogaster white gene from chromosomal position-effects. EMBO J. 1993, 12, 435–442.
48. MacDonald, W.A.; Menon, D.; Bartlett, N.J.; Sperry, G.E.; Rasheva, V.; Meller, V.; Lloyd, V.K. The drosophila homolog of the mammalian imprint regulator, CTCF, maintains the maternal genomic imprint in drosophila melanogaster. BMC Biol. 2010, 8, 105.
49. Ohtsuki, S.; Levine, M. GAGA mediates the enhancer blocking activity of the eve promoter in the drosophila embryo. Genes Dev. 1998, 12, 3325–3330.
50. Gaszner, M.; Vazquez, J.; Schedl, P. The Zw5 protein, a component of the scs chromatin domain boundary, is able to block enhancer-promoter interaction. Genes Dev. 1999, 13, 2098–2107.
51. Aoki, T.; Sarkeshik, A.; Yates, J.; Schedl, P. Elba, a novel developmentally regulated chromatin boundary factor is a hetero-tripartite DNA binding complex. eLife 2012, 1, 1–24.
52. Bag, I.; Dale, R.K.; Palmer, C.; Lei, E.P. The zinc-finger protein CLAMP promotes gypsy chromatin insulator function in Drosophila. J. Cell Sci. 2019, 132, 6.
53. Cuartero, S.; Fresán, U.; Reina, O.; Planet, E.; Espinàs, M.L. Ibf1 and Ibf2 are novel CP190-interacting proteins required for insulator function. EMBO J. 2014, 33, 637–647.
54. Gerasimova, T.I.; Gdula, D.A.; Gerasimov, D.V.; Simonova, O.; Corces, V.G. A drosophila protein that imparts directionality on a chromatin insulator is an enhancer of position-effect variegation. Cell 1995, 82, 587–597.
55. Savitsky, M.; Kim, M.; Kravchuk, O.; Schwartz, Y.B. Distinct roles of chromatin insulator proteins in control of the Drosophila bithorax complex. Genetics 2016, 202, 601–617.
56. Bartkuhn, M.; Straub, T.; Herold, M.; Herrmann, M.; Rathke, C.; Saumweber, H.; Gilfillan, G.D.; Becker, P.B.; Renkawitz, R. Active promoters and insulators are marked by the centrosomal protein 190. EMBO J. 2009, 28, 877–888.
57. Pherson, M.; Misulovin, Z.; Gause, M.; Dorsett, D. Cohesin occupancy and composition at enhancers and promoters are linked to DNA replication origin proximity in Drosophila. Genome Res. 2019, 29, 602–612.
58. Parelho, V.; Hadjur, S.; Spivakov, M.; Leleu, M.; Sauer, S.; Gregson, H.C.; Jarmuz, A.; Canzonetta, C.; Webster, Z.; Nesterova, T.; et al. Cohesins functionally associate with CTCF on mammalian chromosome arms. Cell 2008, 132, 422–433.
59. Rubio, E.D.; Reiss, D.J.; Welcsh, P.L.; Disteche, C.M.; Filippova, G.N.; Baliga, N.S.; Aebersold, R.; Ranish, J.A.; Krumm, A. CTCF physically links cohesin to chromatin. Proc. Natl. Acad. Sci. USA. 2008, 105, 8309–8314.
60. Holohan, E.E.; Kwong, C.; Adryan, B.; Bartkuhn, M.; Herold, M.; Renkawitz, R.; Russell, S.; White, R. CTCF genomic binding sites in Drosophila and the organisation of the bithorax complex. PLoS Genet. 2007, 3, 1211–1222.
61. Misulovin, Z.; Schwartz, Y.B.; Li, X.Y.; Kahn, T.G.; Gause, M.; MacArthur, S.; Fay, J.C.; Eisen, M.B.; Pirrotta, V.; Biggin, M.D.; et al. Association of cohesin and Nipped-B with transcriptionally active regions of the drosophila melanogaster genome. Chromosoma 2008, 117, 89–102.
62. Karch, F.; Galloni, M.; Sipos, L.; Gausz, J.; Gyurkovics, H.; Sched, P. Mcp and Fab-7: Molecular analysis of putative boundaries of cis-regulatory domains in the bithorax complex of drosophila melanogaster. Nucleic Acids Res. 1994, 22, 3138–3146.
63. Cavalli, G.; Paro, R. The Drosophila Fab-7 chromosomal element conveys epigenetic inheritance during mitosis and meiosis. Cell 1998, 93, 505–518.
64. Pérez-Lluch, S.; Cuartero, S.; Azorín, F.; Espinàs, M.L. Characterization of new regulatory elements within the drosophila bithorax complex. Nucleic Acids Res. 2008, 36, 6926–6933.
65. Moon, H.; Filippova, G.; Loukinov, D.; Pugacheva, E.; Chen, Q.; Smith, S.T.; Munhall, A.; Grewe, B.; Bartkuhn, M.; Arnold, R.; et al. CTCF is conserved from Drosophila to humans and confers enhancer blocking of the Fab-8 insulator. EMBO Rep. 2005, 6, 165–170.
66. Mohan, M.; Bartkuhn, M.; Herold, M.; Philippen, A.; Heinl, N.; Bardenhagen, I.; Leers, J.; White, A.R.; Renkawitz-Pohl, R.; Saumweber, H.; et al. The drosophila insulator proteins CTCF and CP190 link enhancer blocking to body patterning. EMBO J. 2007, 26, 4203–4214.
67. 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, 1333–1356.
68. Sipos, L.; Gyurkovics, H. Long-distance interactions between enhancers and promoters: The case of the Abd-B domain of the Drosophila bithorax complex. FEBS J. 2005, 272, 3253–3259.
69. Kyrchanova, O.; Toshchakov, S.; Podstreshnaya, Y.; Parshikov, A.; Georgiev, P. Functional interaction between the Fab-7 and Fab-8 boundaries and the upstream promoter region in the drosophila Abd-B gene. Mol. Cell. Biol. 2008, 28, 4188–4195.
70. Postika, N.; Metzler, M.; Affolter, M.; Müller, M.; Schedl, P.; Georgiev, P.; Kyrchanova, O. Boundaries mediate long-distance interactions between enhancers and promoters in the drosophila bithorax complex. PLoS Genet. 2018, 14, 1–21.
71. Heger, P.; Marin, B.; Bartkuhn, M.; Schierenberg, E.; Wiehe, T. The chromatin insulator CTCF and the emergence of metazoan diversity. Proc. Natl. Acad. Sci. USA 2012, 109, 17507–17512.
72. Heger, P.; George, R.; Wiehe, T. Successive gain of insulator proteins in arthropod evolution. Evolution (N. Y.) 2013, 67, 2945–2956.
73. Seller, C.A.; Cho, C.-Y.; O’Farrell, P.H. Rapid embryonic cell cycles defer the establishment of heterochromatin by Eggless/SetDB1 in drosophila. Genes Dev. 2019, 33, 403–417.
74. Armstrong, R.L.; Duronio, R.J. Phasing in heterochromatin during development. Genes Dev. 2019, 33, 379–381.
75. Fuks, F.; Hurd, P.J.; Deplus, R.; Kouzarides, T. The DNA methyltransferases associate with HP1 and the SUV39H1 histone methyltransferase. Nucleic Acids Res. 2003, 31, 2305–2312.
76. Muramatsu, D.; Kimura, H.; Kotoshiba, K.; Tachibana, M.; Shinkai, Y. Pericentric H3K9me3 Formation by HP1 Interaction-defective Histone Methyltransferase Suv39h1. Cell Struct. Funct. 2016, 41, 145–152.
77. Eissenberg, J.C.; Elgin, S.C. The HP1 protein family: Getting a grip on chromation. Curr. Opin. Genet. Dev. 2000, 10, 204.
78. Eissenberg, J.C.; Elgin, S.C.R. HP1a: A structural chromosomal protein regulating transcription. Trends Genet. 2014, 30, 103–110.
79. Hwang, K.K.; Eissenberg, J.C.; Worman, H.J. Transcriptional repression of euchromatic genes by Drosophila heterochromatin protein 1 and histone modifiers. Proc. Natl. Acad. Sci. USA 2001, 98, 11423–11427.
80. Singh, P.B.; Georgatos, S.D. HP1: Facts, open questions, and speculation. J. Struct. Biol. 2002, 140, 10–16.
81. Reuter, G.; Giarre, M.; Farah, J.; Gausz, J.; Spierer, A.; Spierer, P. Dependence of position-effect variegation in Drosophila on dose of a gene encoding an unusual zinc-finger protein. Nature 1990, 6263, 219–223.
82. Tschiersch, B.; Hofmann, A.; Krauss, V.; Dorn, R.; Korge, G.; Reuter, G. The protein encoded by the Drosophila position-effect variegation suppressor gene Su(var)3-9 combines domains of antagonistic regulators of homeotic gene complexes. EMBO J. 1994, 13, 3822–3831.
83. Hoskins, R.A.; Smith, C.D.; Carlson, J.W.; Carvalho, A.B.; Halpern, A.; Kaminker, J.S.; Kennedy, C.; Mungall, C.; Sullivan, B.A.; Sutton, G.; et al. Heterochromatic sequences in a drosophila whole-genome shotgun assembly. Genome Biol. 2002, 3, 1–16.
84. Hoskins, R.A.; Carlson, J.W.; Kennedy, C.; Acevedo, D.; Evans-Holm, M.; Frise, E.; Wan, K.H.; Park, S.; Mendez-Lago, M.; Rossi, F.; et al. Sequence finishing and mapping of drosophila melanogaster heterochromatin. Science 2007, 316, 1625–1628.
85. Ciavatta, D.; Rogers, S.; Magnuson, T. Drosophila CTCF Is Required for Fab-8 enhancer blocking activity in S2 Cells. J. Mol. Biol. 2007, 373, 233–239.
86. Bonchuk, A.; Maksimenko, O.; Kyrchanova, O.; Ivlieva, T.; Mogila, V.; Deshpande, G.; Wolle, D.; Schedl, P.; Georgiev, P. Functional role of dimerization and CP190 interacting domains of CTCF protein in drosophila melanogaster. BMC Biol. 2015, 13, 1–23.
87. Brower-Toland, B.; Riddle, N.C.; Jiang, H.; Huisinga, K.L.; Elgin, S.C.R. Multiple SET methyltransferases are required to maintain normal heterochromatin domains in the genome of drosophila melanogaster. Genetics 2009, 181, 1303–1319.
88. Meyer-Nava, S.; Torres, A.; Zurita, M.; Valadez-Graham, V. Molecular effects of dADD1 misexpression in chromatin organization and transcription. BMC Mol. Cell Biol. 2020, 2, 1–17.
89. Strom, A.R.; Emelyanov, A.V.; Mir, M.; Fyodorov, D.V.; Darzacq, X.; Karpen, G.H. Phase separation drives heterochromatin domain formation. Nature 2017, 547, 241–245.
90. Ishida, T.; Kinoshita, K. PrDOS: Prediction of disordered protein regions from amino acid sequence. Nucleic Acids Res. 2007, 35, 460–464.
91. Frydrychova, R.C.; Biessmann, H.; Mason, J.M. Regulation of telomere length in Drosophila. Cytogenet. Genome Res. 2009, 122, 356–364.
92. Gibbons, R.J.; Picketts, D.J.; Villard, L.; Higgs, D.R. Mutations in a putative global transcriptional regulator cause X-linked mental retardation with α-thalassemia (ATR-X syndrome). Cell 1995, 80, 837–845.
93. Sadic, D.; Schmidt, K.; Groh, S.; Kondofersky, I.; Ellwart, J.; Fuchs, C.; Theis, F.J.; Schotta, G. Atrx promotes heterochromatin formation at retrotransposons. EMBO Rep. 2015, 16, 836–850.
94. Valle-García, D.; Qadeer, Z.A.; McHugh, D.S.; Ghiraldini, F.G.; Chowdhury, A.H.; Hasson, D.; Dyer, M.A.; Recillas-Targa, F.; Bernstein, E. ATRX binds to atypical chromatin domains at the 3′ exons of zinc finger genes to preserve H3K9me3 enrichment. Epigenetics 2016, 11, 398–414.
95. de Wit, E.; Greil, F.; van Steensel, B. High-resolution mapping reveals links of HP1 with active and inactive chromatin components. PLoS Genet. 2007, 3, 0346–0357.
96. Ilyin, A.A.; Stolyarenko, A.D.; Klenov, M.S.; Shevelyov, Y.Y. Various modes of HP1a interactions with the euchromatic chromosome arms in Drosophila ovarian somatic cells. Chromosoma 2020, doi:10.1007/s00412-020-00738-5.
97. Li, Y.; Danzer, J.R.; Alvarez, P.; Belmont, A.S.; Wallrath, L.L. Effects of tethering HP1 to euchromatic regions of the Drosophila genome. Development 2003, 130, 1817–1824.
98. Piacentini, L.; Fanti, L.; Berloco, M.; Perrini, B.; Pimpinelli, S. Heterochromatin protein 1 (HP1) is associated with induced gene expression in Drosophila euchromatin. J. Cell Biol. 2003, 161, 707–714.
99. Petesch, S.J.; Lis, J.T. Rapid, transcription-independent loss of nucleosomes over a large chromatin domain at Hsp70 Loci. Cell 2008, 134, 74–84.
100. Schneiderman, I.J.; Orsi, G.A.; Hughes, K.T.; Loppin, B.; Ahmad, K. Nucleosome-depleted chromatin gaps recruit assembly factors for the H3.3 histone variant. Proc. Natl. Acad. Sci. USA 2012, 109, 19721–19726.
101. Lu, B.Y.; Emtage, P.C.; Duyf, B.J.; Hilliker, A.J.; Eissenberg, J.C. heterochromatin protein 1 is required for the normal expression of two heterochromatin genes in drosophila. Genetics 2000, 155, 699–708.
102. Danzer, J.R.; Wallrath, L.L. Mechanisms of HP1-mediated gene silencing in Drosophila. Development 2004, 131, 3571–3580.
103. de Lucia, F.; Ni, J.Q.; Vaillant, C.; Sun, F.L. HP1 modulates the transcription of cell-cycle regulators in drosophila melanogaster. Nucleic Acids Res. 2005, 33, 2852–2858.
104. Minc, E.; Courvalin, J.; Buendia, B. HP1Ɣ associates associates with euchromatin and heterochromatin in mammalian nuclei and chromosomes. Cytogenet Cell Genet. 2005, 284, 279–284.
105. Vakoc, C.R.; Mandat, S.A.; Olenchock, B.A.; Blobel, G.A. Histone H3 lysine 9 methylation and HP1γ are associated with transcription elongation through mammalian chromatin. Mol. Cell 2005, 19, 381–391.
106. Kwon, S.H.; Florens, L.; Swanson, S.K.; Washburn, M.P.; Abmayr, S.M.; Workman, J.L. Heterochromatin protein 1 (HP1) connects the FACT histone chaperone complex to the phosphorylated CTD of RNA polymerase II. Genes Dev. 2010, 24, 2133–2145.
107. Lee. Y.C.G.; Ogiyama, Y.; Martins, N.M.C; Beliveau, B.J.; Acevedo, D.; Wu, C-T.Cavalli, G.; Karpen, G.H.; et al. Pericentromeric heterochromatin is hierarchically organized and spatially contacts H3K9me2 islands in euchromatin. PLoS Genet. 2020, 16, 1–27.