Nuclear localization of protein phosphatase 5 is dependent on the carboxy-terminal region

AbstractEndogenous and overexpressed protein phosphatase 5 (PP5) localizes to the nucleus and cytoplasm of HeLa cells, while the overexpressed TPR domain of PP5 is restricted to the cytoplasm. Deletion and mutational analysis of human PP5 demonstrates that the C-terminal amino acids 420–499 are essential for nuclear localization and PP5 activity is not required. Since the phosphatase domain terminates at 473, these studies suggest that the highly conserved section (476–491) with the eukaryotic consensus FXAVPHPXΦXPMAYAN is required for nuclear localization of PP5. Bacterially expressed PP5 is inhibited by several tumor promoters but not by the anticancer drug fostriecin

Quantitation of protein phosphatase 1 and 2A in extracts of the budding yeast and fission yeast

újratöltve - bibKLT0009701

Expression of protein phosphatase 1 during the asexual development of Neurospora crassa

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Structural insights into the pSer/pThr dependent regulation of the SHP2 tyrosine phosphatase in insulin and CD28 signaling

Serine/threonine phosphorylation of insulin receptor substrate (IRS) proteins is well known to modulate insulin signaling. However, the molecular details of this process have mostly been elusive. While exploring the role of phosphoserines, we have detected a direct link between Tyr-flanking Ser/Thr phosphorylation sites and regulation of specific phosphotyrosine phosphatases. Here we present a concise structural study on how the activity of SHP2 phosphatase is controlled by an asymmetric, dual phosphorylation of its substrates. The structure of SHP2 has been determined with three different substrate peptides, unveiling the versatile and highly dynamic nature of substrate recruitment. What is more, the relatively stable pre-catalytic state of SHP2 could potentially be useful for inhibitor design. Our findings not only show an unusual dependence of SHP2 catalytic activity on Ser/Thr phosphorylation sites in IRS1 and CD28, but also suggest a negative regulatory mechanism that may also apply to other tyrosine kinase pathways as well

Whole mitochondrial genome diversity in two Hungarian populations.

Complete mitochondrial genomics is an effective tool for studying the demographic history of human populations, but there is still a deficit of mitogenomic data in European populations. In this paper, we present results of study of variability of 80 complete mitochondrial genomes in two Hungarian populations from eastern part of Hungary (Szeged and Debrecen areas). The genetic diversity of Hungarian mitogenomes is remarkably high, reaching 99.9% in a combined sample. According to the analysis of molecular variance (AMOVA), European populations showed a low, but statistically significant level of between-population differentiation (Fst = 0.61%, p = 0), and two Hungarian populations demonstrate lack of between-population differences. Phylogeographic analysis allowed us to identify 71 different mtDNA sub-clades in Hungarians, sixteen of which are novel. Analysis of ancestry-informative mtDNA sub-clades revealed a complex genetic structure associated with the genetic impact of populations from different parts of Eurasia, though the contribution from European populations is the most pronounced. At least 8% of ancestry-informative haplotypes found in Hungarians demonstrate similarity with East and West Slavic populations (sub-clades H1c23a, H2a1c1, J2b1a6, T2b25a1, U4a2e, K1c1j, and I1a1c), while the influence of Siberian populations is not so noticeable (sub-clades A12a, C4a1a, and probably U4b1a4)