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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).

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.

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.

The gene and cDNA of a novel protein phosphatase were cloned from Neurospora crassa. The pzl-1 gene encompasses three introns and is localized to the left arm of chromosome I between cyt-21 and Fsr-12. It encodes a protein of 58.3 kDa containing a Ser/Pro rich N-terminal segment, and a C-terminal domain that is similar to the catalytic subunit of type 1 protein phosphatases. The first 51 amino acid residues, including a potential N-myristoylation site, as well as the C-terminal domain (about 300 residues) have a high level of sequence identity with yeast PPZ phosphatases. However, residues 52-208 do not share high similarity with other proteins. The mRNA of pzl-1 was detected in all phases of asexual development of the filamentous fungus.

Rapid evolution of wireless networking has provided wide-scale of different wireless access technologies like Bluetooth, ZigBee, 802.11a/b/g, DSRC, 3G UMTS, LTE, WiMAX, etc. The complementary characteristic of the above architectures motivates next generation network operators to integrate them in a supplementary and overlapping manner. Recent wireless devices are equipped with multiple interfaces, thus enabling concurrent communication sessions. With the advance of such heterogeneous structures - and considering that users are often running applications simultaneously - the traditional per-host mobility management approach cannot be the optimal solution for handling connection changes. Instead, the concept of per-application mobility management is to be introduced, where a dedicated interface (i.e. access network) is selected by each application according to its QoS prerequisites and the actual networking conditions. Aiming to benefit from this novel concept in practice, in this paper we designed and evaluated a HIP-based per-application mobility management platform founded on the promising Host Identity Protocol (HIP) and the cross-layer building blocks closely incorporating with it.

The catalytic activities of protein phosphatase 1, 2A, 2B, and 2C were detected in crude extracts of Caenorhabditis elegans with different phosphoprotein substrates and specific inhibitors or activators. The enzymological properties of protein phosphatase 2B as well as those of the catalytic subunits of protein phosphatase 1 and protein phosphatase 2A were determined after partial purification. Gene fragments encoding the catalytic subunits of the protein phosphatase 1-2A-2B superfamily were amplified by polymerase chain reaction and were identified by DNA sequencing. Besides the homologs of protein phosphatase 1, 2B, and X, five protein phosphatase 1-type sequences and four novel protein phosphatase sequences were found. Our data, together with the results of the C. elegans genome project, suggest that this nematode contains an extensive family of Ser/Thr specific protein phosphatases including several up to now biochemically uncharacterized members.

Serine/threonine protein phosphatases are also involved in the control of cell division. The aim of the present study was to compare the activity of protein phosphatase 1 (PP1) and 2A (PP2A) in cell extracts of the budding and fission yeast, made at different phases of growth. The activities of PP1 and PP2A toward phosphorylase were similar in extracts of S. cerevisiae. In S. pombe extracts, PP1 was responsible for more than 80% of the phosphorylase phosphatase activity. Ammonium sulfate-ethanol treatment increased the specific activity of the phosphatases and the percentage of PP2A in S. cerevisiae extracts. No increase in the proportion of PP2A was observed upon the same treatment of S. pombe extracts. The above results were confirmed by fractionation of PP1 and PP2A activities on a heparin-Sepharose column. The proportion of PP1 and PP2A activities did not change significantly during exponential cell growth but cells from stationary phase exhibited lower phosphatase activities. These results may indicate a lower level of expression of the PP2A genes in S. pombe and/or differences in the structure of the holoenzymes or their regulators in the two genera.

Endogenous 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.