Disease relevance of PPP1R10

• We report in this study that, when nontransformed CV1 epithelial cells and Hs578T breast cancer cells are treated with the chemotherapeutic agent cytosine arabinoside (Ara-C), Thr-821 of Rb is rapidly dephosphorylated concomitant with dissociation of the PP1 regulatory subunit PNUTS (phosphatase nuclear targeting subunit) from PP1 enzyme [1].
• Promoter analysis confirmed the presence of hypoxia response elements in the promoter region of the PNUTS gene, which respond to hypoxia and forced expression of hypoxia-inducible factor 1 alpha [2].

Psychiatry related information on PPP1R10

• We also characterize the protein expression pattern for PNUTS by Western blotting and immunohistochemistry with PNUTS antibody in Alzheimer's disease (AD) brains and age-matched control brains [3].

High impact information on PPP1R10

• Our studies have provided an extensive map of functional elements in the 5' region (nuncleotides 7259 to 7510) of the human papillomavirus type 31 URR that are involved in the regulation of p99 promoter activity at different stages of the viral life cycle [4].
• The C-terminus of p99 contains seven RGG RNA-binding motifs, followed by eleven decapeptide repeats containing six or more of the following conserved residues (GHRPHEGPGG), and finally a putative zinc finger domain [5].
• We have purified a form of protein phosphatase 1 (PP1) from HeLa cell nuclei, in which the phosphatase is complexed to a regulatory subunit termed p99 [5].
• Furthermore, the effect of extracellular zinc on the expression of the zinc finger protein PNUTS (protein phosphatase 1 nuclear targeting subunit 10) was investigated and revealed an upregulation of PNUTS expression in the presence of 1 microM extracellular zinc by 294% when compared to incubation in zinc free medium [6].
• CAT 53: a protein phosphatase 1 nuclear targeting subunit encoded in the MHC Class I region strongly expressed in regions of the brain involved in memory, learning, and Alzheimer's disease [3].

Biological context of PPP1R10

• A novel gene (named FB19) has been identified within the HLA class I region at human chromosome 6p21 [7].
• We present the genomic organization of CAT 53, localize specific sites of mRNA transcription in thin sections of mouse brain by in-situ hybridization, and perform a structural analysis of the peptide domains [3].
• We identified CAT 53 by cDNA hybridization selection as an expressed sequence tag (EST), located in the vicinity of HLA-C and designated as CAT (for HLA-C associated transcript) 53 [3].
• In interphase cytosolic extract, ATP-dependent decondensation of prometaphase chromosomes is blocked by PP1-specific inhibitors [8].
• We hypothesize that targeting of PNUTS to reforming nuclei in telophase may be a part of a signalling event promoting chromatin decondensation as cells re-enter interphase [8].

Anatomical context of PPP1R10

• Very high expression of CAT 53 was found mainly in the hippocampus, frontal, and entorhinal cortex of control brains and in the neurofibrillary tangles of AD brain [3].
• Immunofluorescence analysis shows that PNUTS is targeted to the reforming nuclei in telophase following the assembly of nuclear membranes and concomitantly with chromatin decondensation [8].

Associations of PPP1R10 with chemical compounds

• PP1 (protein phosphatase-1) is a serine/threonine phosphatase involved in mitosis exit and chromosome decondensation [8].

Analytical, diagnostic and therapeutic context of PPP1R10

• We report here the cloning and characterisation of the p99 component. p99 mRNA is widely expressed in human tissues and immunofluorescence analysis with anti-p99 antibodies showed a punctate nucleoplasmic staining with additional accumulations within the nucleolus [5].

References