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).

HVS-I polymorphism screening of ancient human mitochondrial DNA provides evidence for N9a discontinuity and East Asian haplogroups in the Neolithic Hungary.

Analysis of mitochondrial mutations in the HVS-I region is an effective method for ancient human populational studies. Discontinuous haplotype data between the first farmers and contemporary Europeans has been described before. Our contribution is based on a survey initiated on the Neolithic skeletons from Hungarian archaeological sites in the Alföld. This Lowland, the Hungarian Plain, is well excavated as an important region for spread of Neolithic culture from Near East and Balkans toward Central and Western Europe, started circa 8000 years ago. HVS-I sequences from nt15977 to nt16430 of 11 such specimens with sufficient mitochondrial DNA preservation among an extended Neolithic collection were analysed for polymorphisms, identifying 23 different ones. After assigning all single-nucleotide polymorphisms, a novel, N9a, N1a, C5, D1/G1a, M/R24 haplogroups were determined. On mitochondrial control mutations at nt16257 and nt16261, polymorphic PCRs were carried out to assess their distribution in remains. Neolithic data set was compared with contemporary Vác samples and references, resulting in higher frequency of N9a in Alföld as a remarkable genetic discontinuity. Our investigation is the first to study mutations form Neolithic of Hungary, resulting in an outcome of Far Eastern haplogroups in the Carpathian Basin. It is worth further investigation as a non-descendant theory, instead of a continuous population history, supporting genetic gaps between ancient and recent human populations.

Human protein phosphatase 5 dissociates from heat-shock proteins and is proteolytically activated in response to arachidonic acid and the microtubule-depolymerizing drug nocodazole.

Ppp5 (protein phosphatase 5) is a serine/threonine protein phosphatase that has been conserved throughout eukaryotic evolution. In mammalian cells, FLAG-tagged Ppp5 and endogenous Ppp5 are found to interact with endogenous Hsp (heat-shock protein) 70, as well as Hsp90. Incubation of cells with arachidonic acid or the microtubule-depolymerizing agent, nocodazole, causes loss of interaction of Hsp70 and Hsp90 with FLAG-tagged Ppp5 and increase of Ppp5 activity. In response to the same treatments, endogenous Ppp5 undergoes proteolytic cleavage of the N- and C-termini, with the subsequent appearance of high-molecular-mass species. The results indicate that Ppp5 is activated by proteolysis on dissociation from Hsps, and is destroyed via the proteasome after ubiquitination. Cleavage at the C-terminus removes a nuclear localization sequence, allowing these active cleaved forms of Ppp5 to translocate to the cytoplasm. The response of Ppp5 to arachidonic acid and nocodazole suggests that Ppp5 may be required for stress-related processes that can sometimes cause cell-cycle arrest, and leads to the first description for in vivo regulation of Ppp5 activity.

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

We cloned and sequenced the cDNA and the gene encoding the catalytic subunit of protein phosphatase 1 from the filamentous fungus Neurospora crassa. The gene, designated ppp-1 (phosphoprotein phosphatase 1), was mapped by restriction fragment length polymorphism to linkage group III, in the vicinity of con-7 and trp-1. The expression of the gene was monitored by reverse transcriptase and polymerase chain reactions, by Western blotting, and by protein phosphatase activity assays in synchronized cultures. Transcripts of ppp-1 were detected in the dormant conidia. The abundance of ppp-1 mRNA, Ppp-1 protein, and the activity of protein phosphatase 1 increased during germination and subsequent hyphal elongation as well as during the early stages of aerial mycelium formation.