Disease relevance of JARID1B

• A novel gene (PLU-1) containing highly conserved putative DNA/chromatin binding motifs is specifically up-regulated in breast cancer [1].
• Isolation and chromosomal localization of a new human retinoblastoma binding protein 2 homologue 1a (RBBP2H1A) [2].
• The properties of homologues to several of the identified tumor-antigens, especially PLU-1, SCP-1, DNEL2, CLOCK, and PIASx-alpha, suggest further investigation of their possible function in malignant melanoma [3].
• Analysis by histological type indicated that survivin showed the highest positivity in ductal carcinoma and that survivin and PLU-1 showed the same positivity rate (40.0%) in the five carcinomas classified histologically as either solid-tubular or mucinous [4].

High impact information on JARID1B

• Here we demonstrate that the JARID1 proteins RBP2, PLU1, and SMCX are histone demethylases specific for di- and trimethylated histone 3 lysine 4 (H3K4) [5].
• Similarly, the anti-P. vivax monoclonal immunoprecipitated two proteins of 51,000 mol wt (Pv51) and 45,000 mol wt (Pv45) from extracts of metabolically labeled P. vivax sporozoites [6].
• Human PLU-1 Has transcriptional repression properties and interacts with the developmental transcription factors BF-1 and PAX9 [7].
• PLU-1 is a large (1544 amino acids) nuclear protein that is highly expressed in breast cancers and is proposed to function as a regulator of gene expression [7].
• Transient transfection of cell lines with MYC-tagged PLU-1 showed the protein to be localized in the nucleus and associated with discrete foci [1].

Biological context of JARID1B

• A fragment of the PLU-1 cDNA was identified by differentially screening a fetal brain library with cDNAs prepared from ce-1 cells (a human mammary epithelial cell line overexpressing c-ErbB2) treated or untreated with the antibody 4D5, which inhibits c-ErbB2 phosphorylation [1].

Anatomical context of JARID1B

• Although expression of PLU-1 in ce-1 cells is regulated by signaling from c-ErbB2, the gene is expressed in all the breast cancer cell lines examined, in cells cultured from primary breast cancers, and in the invasive and in situ components of primary breast cancers [1].
• Our results suggest that the PLU-1 protein may belong to the class of testis/cancer antigens [8].

Associations of JARID1B with chemical compounds

• Cloning and sequencing of the downstream region of the CRG1 gene led to the discovery of an adjacent gene ( PUT1) encoding a putative uracil transporter [9].

Other interactions of JARID1B

• Because both BF-1 and PAX proteins interact with members of the groucho co-repressor family, it is plausible that PLU-1 has a role in groucho-mediated transcriptional repression [7].
• Immunohistochemical analysis with the antiserum alpha-PLU-1C confirmed the nuclear localisation of PLU-1. alpha-PLU-1C also reacted with the mouse homologue of PLU-1 (mPlu-1) but not with the closest family member, RBP2 [8].
• Using a NotI linking clone NR-025 as a probe, we isolated a novel putative member of the RB binding protein family, namely a human retinoblastoma binding protein 2 homologue (RBBP2H1A) [2].

Analytical, diagnostic and therapeutic context of JARID1B

• Using Western blot analysis, PLU-1 was shown to be well expressed in breast cancers and breast cancer cell lines, while it was not detected in a range of normal adult tissues [8].
• Besides 2 known cancer-germline genes (SCP-1 and PLU-1), the other isolated antigens were expressed in a non-tumor-specific fashion as analyzed by virtual Northern blot or RT-PCR [3].

References