Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Three genes on 11p15.5 are known to undergo genomic imprinting. The gene for insulin-like growth factor II (IGF2) is normally expressed from the paternal allele, while H19 and p57KIP2, a cyclin-dependent kinase inhibitor, are expressed from the maternal allele. Five germline balanced chromosomal rearrangement breakpoints from patients with Beckwith-Wiedemann syndrome (BWS) have been mapped to 11p15.5 between p57KIP2 and IGF2, and all are derived from the maternal chromosome. By positional cloning from BWS breakpoints, we have isolated a gene 100 kb and 65 kb centromeric to the proximal end of this BWS breakpoint cluster and p57KIP2, respectively. This gene is homologous to yeast nucleosome assembly protein (NAP1) and to a human homologue of NAP1, and we designate it hNAP2 (human nucleosome assembly protein 2). hNAP2 diverges in its expression pattern from IGF2, H19, and p57KIP2, and it shows biallelic expression in all tissues tested. Thus, hNAP2 is functionally insulated from the imprinting domain of 11p15.
Hum Mol Genet 1996 Nov
PMID:A novel human homologue of yeast nucleosome assembly protein, 65 kb centromeric to the p57KIP2 gene, is biallelically expressed in fetal and adult tissues. 892 2

We have recently cloned the human nucleosome assembly protein 2 (NAP-2). Here, we demonstrate that casein kinase 2 (CKII) from HeLa cell nuclear extracts interacts with immobilized NAP-II, and phosphorylates both NAP-2 and nucleosome assembly protein 1 (NAP-1) in vitro. Furthermore, NAP-1 and NAP-2 phosphorylation in crude HeLa cell extracts is abolished by heparin, a specific inhibitor of CKII. Addition of core histones can stimulate phosphorylation of NAP-1 and NAP-2 by CKII. NAP-2 is also a phosphoprotein in vivo. The protein is phosphorylated at the G0/G1 boundary but it is not phosphorylated in S-phase. Here, we show that NAP-2 is a histone chaperone throughout the cell cycle and that its cell-cycle distribution might be governed by its phosphorylation status. Phosphorylated NAP-2 remains in the cytoplasm in a complex with histones during the G0/G1 transition, whereas its dephosphorylation triggers its transport into the nucleus, at the G1/S-boundary, with the histone cargo, suggesting that binding to histones does not depend on phosphorylation status. Finally, indirect immunofluorescence shows that NAP-2 is present during metaphase of HeLa and COS cells, and its localization is distinct from metaphase chromosomes.
J Mol Biol 2000 Apr 28
PMID:NAP-2: histone chaperone function and phosphorylation state through the cell cycle. 1076 93