Atlas of Genetics and Cytogenetics

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Gene Section Review

BRE (brain and reproductive organ-expressed (TNFRSF1A modulator)) Yiu-Loon Chui, Kenneth Ka-Ho Lee, John Yeuk-Hon Chan Department of Chemical Pathology, The Chinese University of Hong Kong, Hong Kong (YLC), School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong (KKHL), Key Lab of Regenerative Medicine, Ministry of Education, Jinan University, Guang Zhou, Guang Dong, China (JYHC)

Published in Atlas Database: June 2010 Online updated version : http://AtlasGeneticsOncology.org/Genes/BREID839ch2p23.html DOI: 10.4267/2042/44978 This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 2.0 France Licence. © 2011 Atlas of Genetics and Cytogenetics in Oncology and Haematology

undetermined. In mice, alternative splicing occurs only Identity at the 5' region of the gene. The major transcript is Other names: BRCC4; BRCC45 variant 5 (NCBI nomenclature), which encodes the HGNC (Hugo): BRE ubiquitous 383-amino acid protein that is 99% identical to human BRE. The minor transcript variants, unlike Location: 2p23.2 the human counterparts, are expressed differentially Local order: According to GeneLoc and NCBI Map among tissues. Their functions are undetermined Viewer, genes flanking BRE are RBKS 2p23.3 (Ching et al., 2003). (ribokinase) in the minus strand orientation, and Transcription RPL23AP34 2p23.2 (ribosomal protein L23a pseudogene 34) in the positive strand orientation. Exon 1 is non-coding; its flanking sequences are embedded in a CpG island of 1216 bases long. DNA/RNA Transcription start varies over the region between 35 to 112 bases upstream of the last base of exon 1, with the Description most common site at 40 bases upstream. No TATA or The gene spans 448284 bases, telomere to centromere CAAT box is located within 150 bases upstream of any orientation. The first exon is non-coding. In humans, of the transcription start sites. BRE mRNA is expressed six transcript variants are produced by alternative ubiquitously, and was initially found to be highly splicing predominantly at either end of the gene. All expressed in brain, and reproductive organs; hence the human cells examined co-express all of the splice name "BRE" (Li et al., 1995). Subsequent screens variants, but at different ratios to one another. The using human multiple-tissue RNA dot blot and major transcript is αa, also known as variant 3 by NCBI Northern blot revealed highest transcript expression in nomenclature. This transcript encodes the ubiquitous adrenal and heart (Miao et al., 2001). 383-amino-acid protein, designated by NCBI as protein Pseudogene isoform 2 (NP_954661.1) (Ching et al., 2001). No pseudogene found. Functions of all minor transcript variants are

Atlas Genet Cytogenet Oncol Haematol. 2011; 15(3) 255 BRE (brain and reproductive organ-expressed (TNFRSF1A modulator)) Chui YL, et al.

Generation of the major transcript variant of human BRE. Human BRE gene (not drawn in scale) is consisted of 15 exons, three of which are alternatively spliced. The light green boxes, X - Z, are alternative exons which are not present in the major transcript. The asterisked ATG is the translation start. This transcript encodes the major 383-amino-acid BRE protein isoform 2, that has been studied.

immumnohistochemistry and Western blot analysis Protein (Chan et al., 2008). Note Localisation BRE is a 383-amino-acid protein of no identifiable BRE is located in cytoplasm and nucleus. functional domain by sequence homology. No crystal structure of BRE is available. This protein has no Function paralog. The N-terminal region of 333 residues of DNA-repair and anti-apoptosis via regulation of human BRE, which is conserved among vertebrate ubiquitination. BRE was shown able to bind K48- and orthologs, has been classified as a single unique K63-linked polyubiquitin chains (Wang et al., 2009). domain, pfam06113. It has been recently proprosed that BRE and its mouse ortholog are expressed in cytosolic BRE contains 2 ubiquitin E2 variant (UEV) domains and nuclear compartments (Li et al., 2004). In the (Wang et al., 2009). nucleus, BRE is part of the BRCA1-A complex Description involved in DNA repair and maintaining G2/M arrest in BRE is an evolutionarily highly conserved protein with response to DNA damage. BRCA1-A complex consists no homolog within the same species. The major protein of BRCA1, BARD1, Abraxas/Abra1/CCDC98, RAP80, isoform is 383 amino-acids long. Based on BRCC36, BRE, and MERIT40/NBA1 (Dong et al., bioinformatic analysis, BRE was proposed to have two 2003; Sobhian et al., 2007; Feng et al., 2009; Shao et ubiquitin-binding UEV (Ubiquitin E2 variant) domains. al., 2009; Wang et al., 2009). BRE interacts strongly One was located in the N-terminal region between with MERIT40 and is responsible for binding the latter residues 30 and 147. The other one, however, could to the complex of Abraxas, RAP80 and BRCC36 (Feng only be located in the isoform encoded by a rare et al., 2009). BRE may also regulate the K63 transcript variant 1, as the C-terminal one quarter of the deubiquitinase activity of BRCC36 (Sobhian et al., putative domain is encoded by the alternative exon Y 2007). In conjunction with BRCC36, BRE was shown (Wang et al., 2009). Thus, it is not clear whether the to potentiate the E3 activity of BRCA1-BARD1 remaining putative UEV domain sequence from complex (Dong et al., 2003). Furthermore, depletion of residues 275 to 363 of the major BRE isoform is BRE by siRNA sensitized cells to death induced by functional. ionizing irradiation (Dong et al., 2003; Feng et al., 2009). This protein also forms multiprotein BRISC Expression (Brcc36 isopeptidase complex) in the cytoplasm. BRE is ubiquitously expressed. All mammalian cell BRISC, containing at least 3 proteins, lines examined express high levels of BRE. These cell FAM175B/ABRO1, BRCC36 and MERIT40/NBA1, in lines include Jurkat, KRC/Y, HeLa, HepG2, HL60, addition to BRE, specifically cleaves K63-linked MCF7, NIH3T3, NS0, THP-1, and lymphoblastoid polyubiquitin chains (Cooper et al., 2009). It is not CB14022 cells. Among mouse tissues, the expression known whether such cytosolic complex is responsible levels of BRE detected by Western blot analysis for attenuating apoptotic response emanating from the showed the following pattern: lungs = spleen = thymus activated death receptors, TNF-R1 and Fas. BRE also > adrenal > testis = kidney > brain > heart = liver. binds to the cytoplasmic region of TNF-R1 and Fas, as Human hepatocytes express little BRE as detected by well as the death-inducing signaling complex (DISC)

Atlas Genet Cytogenet Oncol Haematol. 2011; 15(3) 256 BRE (brain and reproductive organ-expressed (TNFRSF1A modulator)) Chui YL, et al.

during apoptotic induction (Gu et al., 1998; Li et al., the 5' UTR, are present in the introns. Two 2004). The anti-apoptotic role of BRE has been shown recombination hotspots are located in the introns, one by the increased apoptotic response to TNF-alpha of of which is from position 28271535 to 28276573, HeLa cell line depleted of BRE by siRNA, and the located between coding exons 7 and 8. attenuated response of HeLa and Jurkat to TNF-alpha The other one is from position 28338948 to 28341210, and anti-Fas agonist antibody by over-expression of the located between coding exons 10 and 11. Copy number protein. As over-expression of BRE also reduced polymorphisms (CNP) involving a large contiguous intrinsic apoptotic response induced by stress-related region of 163295 bases encompassing the first 3 coding and genotoxic stimuli, it has been proposed that the exons and the upstream sequence of the neighbouring death receptor-associating BRE inhibits the recruitment ribokinase gene and smaller downstream regions have of mitochondrial apoptotic machinery, which is also been identified (see diagram above) (The necessary for amplifying the death-receptor-initiated International HapMap Consortium, 2003). apoptosis of CD95 type II cell types, which include Somatic HeLa, Jurkat, and hepatocytes (Scaffidi et al., 1998; Engels et al., 2000). Ectopic expression of BRE in One R9L mutation was identified in a lung carcinoma mouse Lewis lung carcinoma cells was shown to cell line, NIH-H2126, and a synonymous mutation promote tumor growth in footpad injection model, but S182S in a clear cell renal cell carcinoma sample, have no effect on cell proliferation in culture condition PD2198a. (Chan et al., 2005). Over-expression of BRE was found in 74% of 123 samples of human hepatocellular Implicated in carcinoma, and the protein expression level correlated Hepatocellular carcinoma (HCC) with poor prognosis. Immortalized human cell lines Note also uniformly express high levels of BRE regardless of Immunohistochemical analysis, supplemented by the tissue origin of these cell lines. Transgenic immunoblotting, has revealed overexpression of BRE expression of BRE in mouse liver attenuated acute in the tumoral regions of 72% of the 123 human HCC fulminant hepatitis induced by anti-Fas antibody, and promoted diethylnitrosamine-induced, but not samples examined. Non-tumoral liver regions, cirrhotic spontaneous, liver tumors (Chan et al., 2008; Chui et or otherwise, expressed little BRE (Chan et al., 2008). al., 2010). Thus, it is likely that BRE over-expression Prognosis enhances tumor survival through its anti-apoptotic The over-expression levels of BRE correlated with activity, rather than initiates tumor formation. poor differentiation of HCC cells and therefore poor Homology prognosis. Cytogenetics No homologous protein of BRE found within the same Not determined. species. Hybrid/Mutated gene Mutations Not determined. Note Abnormal protein According to HapMap genotyped SNP data, there is no No fusion protein reported. SNP polymorphism in any of the coding exons of BRE. Oncogenesis Germinal The transgenic mouse model with liver-specific over- expression of human BRE showed no enhanced According to the current HapMap_rel27 for all the 4 spontaneous tumor development, indicating that BRE populations (CEU, CHB, JPT and YRI), the number of over-expression alone is not tumorigenic. These mice, nucleotide positions in BRE gene with HapMap however, showed significant attenuation of liver genotyped SNP is 453. Given the size of BRE gene of apoptosis induced by injection anti-Fas agonist 448284 bases long, the number of bases with SNP fits antibody. These findings indicate that the over- well to the average genome-wide figure of one SNP per expression of BRE in HCC is related to the anti- 1000 bases (Dutt and Beroukhim, 2007). It is, however, apoptotic activity of the protein which promotes growth noteworthy that no SNP has been found in any of the of the carcinoma (Chan et al., 2008). coding exons. All of the SNPs, except one located in

Copy number polymorphism (CNP) of BRE gene. Regions with CNP are shown in colored boxes. Blue and red indicate copy loss and gain, respectively. Green indicates loss and gain at different segments of the contiguous region. The largest CNP region on the far left

Atlas Genet Cytogenet Oncol Haematol. 2011; 15(3) 257 BRE (brain and reproductive organ-expressed (TNFRSF1A modulator)) Chui YL, et al.

spans the first non-coding and the next 3 coding exons (exons 1, 2, 3 and 4) and extends further upstream into the neighboring ribokinase gene. The copy gain variant at the far right spans the alternative exon Z. Data obtained from HapMap. Recent work on inducing liver carcinoma to the above subunit and its role in DNA repair. Mol Cell. 2003 transgenic mice by neonatal injection of Nov;12(5):1087-99 diethylnitrosamine (DEN) confirmed that BRE over- Li Q, Ching AK, Chan BC, Chow SK, Lim PL, Ho TC, Ip WK, expression in the liver could only promote growth of Wong CK, Lam CW, Lee KK, Chan JY, Chui YL. A death receptor-associated anti-apoptotic protein, BRE, inhibits the already initiated tumor, rather than on initiating mitochondrial apoptotic pathway. J Biol Chem. 2004 Dec tumor formation. Interestingly, the DEN-induced liver 10;279(50):52106-16 tumors of the non-transgenic controls also showed up- Chan BC, Li Q, Chow SK, Ching AK, Liew CT, Lim PL, Lee KK, regulation of endogenous BRE, suggesting that the Chan JY, Chui YL. BRE enhances in vivo growth of tumor BRE is important in liver carcinogenesis through its cells. Biochem Biophys Res Commun. 2005 Jan anti-apoptotic activity (Chui et al., 2010). 14;326(2):268-73 Dutt A, Beroukhim R. Single nucleotide polymorphism array References analysis of cancer. Curr Opin Oncol. 2007 Jan;19(1):43-9 Li L, Yoo H, Becker FF, Ali-Osman F, Chan JY. Identification of Sobhian B, Shao G, Lilli DR, Culhane AC, Moreau LA, Xia B, a brain- and reproductive-organs-specific gene responsive to Livingston DM, Greenberg RA. RAP80 targets BRCA1 to DNA damage and retinoic acid. Biochem Biophys Res specific ubiquitin structures at DNA damage sites. Science. Commun. 1995 Jan 17;206(2):764-74 2007 May 25;316(5828):1198-202 Gu C, Castellino A, Chan JY, Chao MV. BRE: a modulator of Chan BC, Ching AK, To KF, Leung JC, Chen S, Li Q, Lai PB, TNF-alpha action. FASEB J. 1998 Sep;12(12):1101-8 Tang NL, Shaw PC, Chan JY, James AE, Lai KN, Lim PL, Lee KK, Chui YL. BRE is an antiapoptotic protein in vivo and Scaffidi C, Fulda S, Srinivasan A, Friesen C, Li F, Tomaselli overexpressed in human hepatocellular carcinoma. Oncogene. KJ, Debatin KM, Krammer PH, Peter ME. Two CD95 (APO- 2008 Feb 21;27(9):1208-17 1/Fas) signaling pathways. EMBO J. 1998 Mar 16;17(6):1675- 87 Cooper EM, Cutcliffe C, Kristiansen TZ, Pandey A, Pickart CM, Cohen RE. K63-specific deubiquitination by two JAMM/MPN+ Engels IH, Stepczynska A, Stroh C, Lauber K, Berg C, complexes: BRISC-associated Brcc36 and proteasomal Poh1. Schwenzer R, Wajant H, Jänicke RU, Porter AG, Belka C, EMBO J. 2009 Mar 18;28(6):621-31 Gregor M, Schulze-Osthoff K, Wesselborg S. Caspase- 8/FLICE functions as an executioner caspase in anticancer Feng L, Huang J, Chen J. MERIT40 facilitates BRCA1 drug-induced apoptosis. Oncogene. 2000 Sep 21;19(40):4563- localization and DNA damage repair. Genes Dev. 2009 Mar 73 15;23(6):719-28 Ching AK, Li PS, Li Q, Chan BC, Chan JY, Lim PL, Pang JC, Shao G, Patterson-Fortin J, Messick TE, Feng D, Shanbhag N, Chui YL. Expression of human BRE in multiple isoforms. Wang Y, Greenberg RA. MERIT40 controls BRCA1-Rap80 Biochem Biophys Res Commun. 2001 Nov 2;288(3):535-45 complex integrity and recruitment to DNA double-strand breaks. Genes Dev. 2009 Mar 15;23(6):740-54 Miao J, Panesar NS, Chan KT, Lai FM, Xia N, Wang Y, Johnson PJ, Chan JY. Differential expression of a stress- Wang B, Hurov K, Hofmann K, Elledge SJ. NBA1, a new modulating gene, BRE, in the adrenal gland, in adrenal player in the Brca1 A complex, is required for DNA damage neoplasia, and in abnormal adrenal tissues. J Histochem resistance and checkpoint control. Genes Dev. 2009 Mar Cytochem. 2001 Apr;49(4):491-500 15;23(6):729-39 . The International HapMap Project. Nature. 2003 Dec Chui YL, Ching AK, Chen S, Yip FP, Rowlands DK, James AE, 18;426(6968):789-96 Lee KK, Chan JY. BRE over-expression promotes growth of hepatocellular carcinoma. Biochem Biophys Res Commun. Ching AK, Li Q, Lim PL, Chan JY, Chui YL. Expression of a 2010 Jan 15;391(3):1522-5 conserved mouse stress-modulating gene, Bre: comparison with the human ortholog. DNA Cell Biol. 2003 Aug;22(8):497- This article should be referenced as such: 504 Chui YL, Lee KKH, Chan JYH. BRE (brain and reproductive Dong Y, Hakimi MA, Chen X, Kumaraswamy E, Cooch NS, organ-expressed (TNFRSF1A modulator)). Atlas Genet Godwin AK, Shiekhattar R. Regulation of BRCC, a holoenzyme Cytogenet Oncol Haematol. 2011; 15(3):255-258. complex containing BRCA1 and BRCA2, by a signalosome-like

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