BRCA1/BARD1 Ubiquitinate Phosphorylated RNA Polymerase II

Starita, Lea M.; Horwitz, Andrew A.; Keogh, Michael Christopher; Ishioka, Chikashi; Parvin, Jeffrey D.; Chiba, Natsuko

doi:10.1074/jbc.m414020200

Cited by 140 publications

(140 citation statements)

References 62 publications

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“…32 The heterodimer BRCA1/BARD1 promotes its own ubiquitination 33 and ubiquitinates RNA pol II subunit A. 34 The interaction of BRCA1 with RNA pol II 11 and DHX9 35 suggested a role for BARD1 in TCR. The BARD1 gene has been reported to be targeted by somatic 36 and germline [37][38][39] mutations in breast and in ovarian 36,40 cancer cohorts.…”

Section: Introductionmentioning

confidence: 99%

Genetic sequence variations of BRCA1-interacting genes AURKA, BAP1, BARD1 and DHX9 in French Canadian Families with high risk of breast cancer

et al. 2009

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Breast cancer is a heterogeneous disease displaying some degree of familial clustering. Highly penetrant breast cancer susceptibility genes represent approximately 20-25% of the familial aggregation of breast cancer. A significant proportion of this familial aggregation of breast cancer is thus yet to be explained by other breast cancer susceptibility genes. Given the high susceptibility conferred by the two major breast cancer predisposition genes, BRCA1 and BRCA2 and the implication of these genes in many key cellular processes, assessment of genes encoding BRCA1-interacting proteins as plausible breast cancer candidate genes is thus attractive. In this study, four genes encoding BRCA1-interacting proteins were analyzed in a cohort of 96 breast cancer individuals from high-risk non-BRCA1/BRCA2 French Canadian families. Although no deleterious truncating germline mutations or aberrant spliced mRNA species were identified, a total of 10, 4, 11 and 6 variants were found in the AURKA, BAP1, BARD1 and DHX9 genes, respectively. The allele frequency of each variant was further ascertained in a cohort of 98 healthy French Canadian unrelated women and a difference in allele frequency was observed for one BARD1 variant based on single-marker analysis. Haplotype estimation, haplotype blocks and tagging SNPs identification were then performed for each gene, providing a valuable tool for further searches of common disease-associated variants in these genes and therefore further analyses on these genes in larger cohorts is warranted in the search of low-to-moderate penetrance breast cancer susceptibility alleles.

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Section: Introductionmentioning

confidence: 99%

Genetic sequence variations of BRCA1-interacting genes AURKA, BAP1, BARD1 and DHX9 in French Canadian Families with high risk of breast cancer

et al. 2009

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“…K48-linked-polyubiquitination triggers 26S-proteasomal degradation of the targeted protein, whereas mono-and K63-linked-poly-ubiquitinations contribute to functional modifications. BRCA1/BARD1-complex and NEDD4 E3-ubiquitin-ligases as well as ERCC8-complex have been reported to be involved in damage-dependent polyubiquitination and degradation of RNA-polIIo [25][26][27] . To determine whether RNA-polIIo is degraded as a consequence of UVSSA-mediated ubiquitination, we analyzed RNA-polIIo modifications after UV-irradiation followed by treatment with a 26S-proteasomal inhibitor, MG132, in normal, and UV S S-A cells (Fig.…”

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Mutations in UVSSA cause UV-sensitive syndrome and impair RNA polymerase IIo processing in transcription-coupled nucleotide-excision repair

et al. 2012

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We initially performed exome-sequencing 11 of the two UV S S-A patients, Kps3 and XP24KO (details described in Methods, Supplementary Note, Table 2c). The patients were homozygous for c.367A>T mutation in UVSSA, which led to a premature termination, p.Lys123* (Fig. 1a, b). We identified the same homozygous mutation in Kps2 (sib. of Kps3), and a homozygous c.87delG, causing a frameshift p.Ile31Phefs*9, in an Israeli patient UV S S24TA (Fig. 1b, c, Supplementary Note, Supplementary Fig. 1). The identified mutations are summarized in Fig. 1d. We did not detect the 80kDa UVSSA protein in any of the UV S S-A patients (Fig. 1e). We additionally examined several mild xeroderma pigmentosum (XP) cases; in one such case, XP70TO 12 (Supplementary Table 1), we identified a homozygous p.Cys32Arg, in the UVSSA (Fig. 1c, d), implying that XP70TO is also in the UV S S-A group. The mutant protein was stably expressed in XP70TO cells (Fig. 1f, Supplementary Fig. 2a-d). 4Allele frequencies of the identified mutations in a control population were examined (Supplementary Note, Supplementary Fig. 3a). Haploinsufficiency for UVSSA is negligible as the parents of Kps2/Kps3 showed no symptoms 4 . In parallel with exome-sequencing, we performed whole-genome SNP-genotyping to identify runs-of-homozygosity (ROH) shared among the patients. We identified three overlapping-ROHs (> 1Mbps) on autosomes, one of which encompasses the UVSSA locus (Fig. 1g, Supplementary Table 3a, b, Supplementary Fig. 3b, c). No chromosome copy number variation was detected (Supplementary Fig. 3d).The above findings strongly suggest that the mutations in UVSSA in the UV S S-A patients are causal for the disease; we therefore, next examined the NER-activities in the UV S S-A cells (Fig. 2). Unscheduled-DNA-synthesis (UDS 13 , defective in XP) was nearly normal; however, RNA-synthesis-recovery (RRS 14 , defective in UV S S and in CS) was reduced in all cell-strains mutated in UVSSA ( Fig. 2a, b; UDS and RRS were measured using a recently-developed rapid non-radioactive system 15,16 ). Similarly, siRNA-based depletion of the UVSSA gene (Fig. 2c) caused a drastic reduction of RRS (Fig. 2d, Supplementary Fig. 4), whereas UDS was unaffected (Fig. 2e). Ectopic-expression of the wild-type UVSSA cDNA in UV S S-A cells restored normal RRS ( Fig. 2f; V5-tagged-UVSSA immunofluorescent-staining shown in Fig. 2g), while it did not affect RRS-level in normal, CS-A, or CS-B cells; neither ERCC8 nor ERCC6 cDNA expression in UV S S-A cells restored the RRS-level.We conclude that KIAA1530/UVSSA is the causal gene for UV S S-A.ERCC8 and ERCC6 genes are responsible for both CS and UV S S 7,8 . To evaluate whether UVSSA mutations may also result in CS-phenotypes, we sequenced 5 the UVSSA gene of 61 CS-patients whose genetic defects had not yet been determined (Supplementary Table 4). We found no obvious mutations except for four novel heterozygous changes. These changes as well as the SNPs, also found in control and UV S S-A individuals, do not affect the RRS-activity (Suppleme...

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“…The BRCA1/BARD1 putative ubiquitination substrates identified to date (histones, ␥-tubulin, RNA polymerase II, and CtIP) cannot explain the association of ubiquitously expressed BRCA1 with the development of tissue-specific breast and ovarian tumors (10)(11)(12)(13)(14). Recently, however, BRCA1 has been shown to interact with and regulate estrogen receptor ␣ (ER␣) and progesterone receptor (PR) transcriptional activation (15)(16)(17).…”

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Estrogen receptor α is a putative substrate for the BRCA1 ubiquitin ligase

Eakin¹,

MacCoss

Finney

et al. 2007

Proc. Natl. Acad. Sci. U.S.A.

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The breast cancer suppressor protein, BRCA1, is a ubiquitin ligase expressed in a wide range of tissues. However, inheritance of a single BRCA1 mutation significantly increases a woman's lifetime chance of developing tissue-specific cancers in the breast and ovaries. Recently, studies have suggested this tissue specificity may be linked to inhibition of estrogen receptor ␣ (ER␣) transcriptional activation by BRCA1. Here, we show that ER␣ is a putative substrate for the BRCA1/BARD1 ubiquitin ligase, suggesting a possible mechanism for regulation of ER␣ activity by BRCA1. Our results show ER␣ is predominantly monoubiquitinated in a reaction that involves interactions with both BRCA1 and BARD1. The regions of BRCA1/BARD1 necessary for ER␣ ubiquitination include the RING domains and at least 241 and 170 residues of BRCA1 and BARD1, respectively. Cancer-predisposing mutations in BRCA1 are observed to abrogate ER␣ ubiquitination. The identification of ER␣ as a putative BRCA1/BARD1 ubiquitination substrate reveals a potential link between the loss of BRCA1/BARD1 ligase activity and tissue-specific carcinoma.breast cancer ͉ ubiquitylation ͉ ubiquitination ͉ steroid hormone receptor T he breast cancer suppressor protein, BRCA1, is essential for early development and associated with a number of cellular processes including cell proliferation, cell cycle progression, apoptosis, and DNA repair/recombination. Inheritance of a single mutation in BRCA1 increases a woman's lifetime risk of developing breast cancer from 1 in 9 to greater than 1 in 2 (1). Additionally, in sporadic nonfamilial cases of breast cancer, BRCA1 expression is significantly reduced, indicating loss of BRCA1 at the protein or mRNA level (2, 3). Therefore, BRCA1 inactivation either through mutation or repression of gene expression is implicated in all forms of breast cancer development.The only known enzymatic activity associated with BRCA1 is its activity as a ubiquitin protein ligase (4). Attachment of ubiquitin to substrates is a versatile method of regulation involved in practically all aspects of cell biology. Substrate ubiquitination involves several steps and a well-known trio of enzymes called ubiquitin activating (E1), ubiquitin conjugating (E2), and ubiquitin ligase (E3). The E3 activity of BRCA1 has been localized to the N-terminal RING domain and depends on heterodimerization with the RING domain of BARD1 (5). Importantly, all BRCA1 cancer-predisposing mutations within the RING domain are observed to eliminate the BRCA1/ BARD1 E3 activity both in vitro and in vivo (5-7). This strongly suggests a link between the tumor suppressor function of BRCA1 and its E3 activity. The ultimate fate of a ubiquitinated substrate depends on both the number of ubiquitins linked in a chain and the ubiquitin chain topology (8). BRCA1/BARD1 has been observed to monoubiquitinate proteins as well as build Lys-6-linked polyubiquitin chains. Lys-6-linked chains are recognized by the 26S proteasome for deubiquitination rather than degradation (9), suggesting ubiquitinat...

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BRCA1/BARD1 Ubiquitinate Phosphorylated RNA Polymerase II

Cited by 140 publications

References 62 publications

Genetic sequence variations of BRCA1-interacting genes AURKA, BAP1, BARD1 and DHX9 in French Canadian Families with high risk of breast cancer

Genetic sequence variations of BRCA1-interacting genes AURKA, BAP1, BARD1 and DHX9 in French Canadian Families with high risk of breast cancer

Mutations in UVSSA cause UV-sensitive syndrome and impair RNA polymerase IIo processing in transcription-coupled nucleotide-excision repair

Estrogen receptor α is a putative substrate for the BRCA1 ubiquitin ligase

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