CTCFL explained

Transcriptional repressor CTCFL also known as BORIS (Brother of Regulator of Imprinted Sites) is a protein that in humans is encoded by the CTCFL gene.^[1]

Function

CCCTC-binding factor (CTCF), an 11-zinc finger factor involved in gene regulation, utilizes different zinc fingers to bind varying DNA target sites. CTCF forms methylation-sensitive insulators that regulate X-chromosome inactivation. Transcriptional repressor CTCFL (this protein) is a paralog of CTCF and appears to be expressed primarily in the cytoplasm of spermatocytes, unlike CTCF which is expressed primarily in the nucleus of somatic cells. CTCF and CTCFL are normally expressed in a mutually exclusive pattern that correlates with resetting of methylation marks during male germ cell differentiation.^[1]

Further reading

• Klenova EM, Morse HC, Ohlsson R, Lobanenkov VV . The novel BORIS + CTCF gene family is uniquely involved in the epigenetics of normal biology and cancer. . Semin. Cancer Biol. . 12 . 5 . 399–414 . 2003 . 12191639 . 10.1016/S1044-579X(02)00060-3 .
• D'Arcy V, Pore N, Docquier F . BORIS, a paralogue of the transcription factor, CTCF, is aberrantly expressed in breast tumours. . Br. J. Cancer . 98 . 3 . 571–9 . 2008 . 18195709 . 10.1038/sj.bjc.6604181 . 2243163 . etal.
• Woloszynska-Read A, James SR, Link PA . DNA methylation-dependent regulation of BORIS/CTCFL expression in ovarian cancer. . Cancer Immun. . 7 . 21 . 2008 . 18095639 . 2935752 . etal.
• Renaud S, Pugacheva EM, Delgado MD . Expression of the CTCF-paralogous cancer-testis gene, brother of the regulator of imprinted sites (BORIS), is regulated by three alternative promoters modulated by CpG methylation and by CTCF and p53 transcription factors. . Nucleic Acids Res. . 35 . 21 . 7372–88 . 2008 . 17962299 . 10.1093/nar/gkm896 . 2175345 . etal.
• Kholmanskikh O, Loriot A, Brasseur F . Expression of BORIS in melanoma: lack of association with MAGE-A1 activation. . Int. J. Cancer . 122 . 4 . 777–84 . 2008 . 17957795 . 10.1002/ijc.23140 . 28681146 . etal. free .
• Risinger JI, Chandramouli GV, Maxwell GL . Global expression analysis of cancer/testis genes in uterine cancers reveals a high incidence of BORIS expression. . Clin. Cancer Res. . 13 . 6 . 1713–9 . 2007 . 17363524 . 10.1158/1078-0432.CCR-05-2569 . etal. free .
• D'Arcy V, Abdullaev ZK, Pore N . The potential of BORIS detected in the leukocytes of breast cancer patients as an early marker of tumorigenesis. . Clin. Cancer Res. . 12 . 20 Pt 1 . 5978–86 . 2006 . 17062669 . 10.1158/1078-0432.CCR-05-2731 . 38340446 . etal.
• Hoffmann MJ, Müller M, Engers R, Schulz WA . Epigenetic control of CTCFL/BORIS and OCT4 expression in urogenital malignancies. . Biochem. Pharmacol. . 72 . 11 . 1577–88 . 2007 . 16854382 . 10.1016/j.bcp.2006.06.020 .
• Hong JA, Kang Y, Abdullaev Z . Reciprocal binding of CTCF and BORIS to the NY-ESO-1 promoter coincides with derepression of this cancer-testis gene in lung cancer cells. . Cancer Res. . 65 . 17 . 7763–74 . 2005 . 16140944 . 10.1158/0008-5472.CAN-05-0823 . etal.
• Rodriguez M, Yu X, Chen J, Songyang Z . Phosphopeptide binding specificities of BRCA1 COOH-terminal (BRCT) domains. . J. Biol. Chem. . 278 . 52 . 52914–8 . 2004 . 14578343 . 10.1074/jbc.C300407200 . free .
• Strausberg RL, Feingold EA, Grouse LH . Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences. . Proc. Natl. Acad. Sci. U.S.A. . 99 . 26 . 16899–903 . 2003 . 12477932 . 10.1073/pnas.242603899 . 139241 . 2002PNAS...9916899M . etal. free .
• Loukinov DI, Pugacheva E, Vatolin S . BORIS, a novel male germ-line-specific protein associated with epigenetic reprogramming events, shares the same 11-zinc-finger domain with CTCF, the insulator protein involved in reading imprinting marks in the soma. . Proc. Natl. Acad. Sci. U.S.A. . 99 . 10 . 6806–11 . 2002 . 12011441 . 10.1073/pnas.092123699 . 124484 . 2002PNAS...99.6806L . etal. free .
• Deloukas P, Matthews LH, Ashurst J . The DNA sequence and comparative analysis of human chromosome 20. . Nature . 414 . 6866 . 865–71 . 2002 . 11780052 . 10.1038/414865a . 2001Natur.414..865D . etal. free .

Notes and References

1. Web site: Entrez Gene: CTCFL CCCTC-binding factor (zinc finger protein)-like.