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1.
The reptile fauna of Romania comprises 23 species, out of which 12 species reach here the limit of their geographic range. We compiled and updated a national database of the reptile species occurrences from a variety of sources including our own field surveys, personal communication from specialists, museum collections and the scientific literature. The occurrence records were georeferenced and stored in a geodatabase for additional analysis of their spatial patterns. The spatial analysis revealed a biased sampling effort concentrated in various protected areas, and deficient in the vast agricultural areas of the southern part of Romania. The patterns of species richness showed a higher number of species in the warmer and drier regions, and a relatively low number of species in the rest of the country. Our database provides a starting point for further analyses, and represents a reliable tool for drafting conservation plans.  相似文献   
2.
Ethnic Belarusians make up more than 80% of the nine and half million people inhabiting the Republic of Belarus. Belarusians together with Ukrainians and Russians represent the East Slavic linguistic group, largest both in numbers and territory, inhabiting East Europe alongside Baltic-, Finno-Permic- and Turkic-speaking people. Till date, only a limited number of low resolution genetic studies have been performed on this population. Therefore, with the phylogeographic analysis of 565 Y-chromosomes and 267 mitochondrial DNAs from six well covered geographic sub-regions of Belarus we strove to complement the existing genetic profile of eastern Europeans. Our results reveal that around 80% of the paternal Belarusian gene pool is composed of R1a, I2a and N1c Y-chromosome haplogroups – a profile which is very similar to the two other eastern European populations – Ukrainians and Russians. The maternal Belarusian gene pool encompasses a full range of West Eurasian haplogroups and agrees well with the genetic structure of central-east European populations. Our data attest that latitudinal gradients characterize the variation of the uniparentally transmitted gene pools of modern Belarusians. In particular, the Y-chromosome reflects movements of people in central-east Europe, starting probably as early as the beginning of the Holocene. Furthermore, the matrilineal legacy of Belarusians retains two rare mitochondrial DNA haplogroups, N1a3 and N3, whose phylogeographies were explored in detail after de novo sequencing of 20 and 13 complete mitogenomes, respectively, from all over Eurasia. Our phylogeographic analyses reveal that two mitochondrial DNA lineages, N3 and N1a3, both of Middle Eastern origin, might mark distinct events of matrilineal gene flow to Europe: during the mid-Holocene period and around the Pleistocene-Holocene transition, respectively.  相似文献   
3.
The mitochondrial contact site and cristae organization system (MICOS) mediates the formation of cristae, invaginations in the mitochondrial inner membrane. The highly diverged MICOS complex of the parasitic protist Trypanosoma brucei consists of nine subunits. Except for two Mic10‐like and a Mic60‐like protein, all subunits are specific for kinetoplastids. Here, we determined on a proteome‐wide scale how ablation of individual MICOS subunits affects the levels of the other subunits. The results reveal co‐regulation of TbMic10‐1, TbMic10‐2, TbMic16 and TbMic60, suggesting that these nonessential, integral inner membrane proteins form an interdependent network. Moreover, the ablation of TbMic34 and TbMic32 reveals another network consisting of the essential, intermembrane space‐localized TbMic20, TbMic32, TbMic34 and TbMic40, all of which are peripherally associated with the inner membrane. The downregulation of TbMic20, TbMic32 and TbMic34 also interferes with mitochondrial protein import and reduces the size of the TbMic10‐containing complexes. Thus, the diverged MICOS of trypanosomes contains two subcomplexes: a nonessential membrane‐integrated one, organized around the conserved Mic10 and Mic60, that mediates cristae formation, and an essential membrane‐peripheral one consisting of four kinetoplastid‐specific subunits, that is required for import of intermembrane space proteins.  相似文献   
4.
A new topological method to measure protein structure similarity   总被引:5,自引:0,他引:5  
A method for the quantitative evaluation of structural similarity between protein pairs is developed that makes use of a Delaunay-based topological mapping. The result of the mapping is a three-dimensional array which is representative of the global structural topology and whose elements can be used to construe an integral scoring scheme. This scoring scheme was tested for its dependence on the protein length difference in a pairwise comparison, its ability to provide a reasonable means for structural similarity comparison within a family of structural neighbors of similar length, and its sensitivity to the differences in protein conformation. It is shown that such a topological evaluation of similarity is capable of providing insight into these points of interest. Protein structure comparison using the method is computationally efficient and the topological scores, although providing different information about protein similarity, correlate well with the distance root-mean-square deviation values calculated by rigid-body structural alignment.  相似文献   
5.
6.
Cardiovascular interventions that restore blood circulation to ischemic areas are accompanied by significant tissue damage, which triggers a vascular remodeling response that may result in restenosis of blood conduits. Early endothelial dysfunction and/or impairment is the early event of a cascade that leads, through an inflammatory response and dedifferentiation of medial smooth muscle cells with abundant deposition of extracellular matrix, to intimal hyperplasia. Here we present the molecular and cellular mechanisms of intimal hyperplasia secondary to vascular injury and discuss the potential role of therapeutic modulation of the intracellular signaling pathways that differentially effect vascular endothelial and smooth muscle cells. The role of mitogen-activated protein kinases (MAPKs) and the outcome of their modulation in these processes are highlighted here as they provide a promising therapeutic target for prevention of restenosis.  相似文献   
7.
The objective of the present study was to examine changes observed in the expression of cytosolic NADP isocitrate dehydrogenase (ICDH) and glucose 6-phosphate dehydrogenase (G6PD) genes, the major implicated genes in ruminant lipogenesis in terms of produce NADPH, during the early post-weaning period in dairy ewes in respect to energy intake, and to further correlate the noted changes with their respective enzymatic activities. A total of 21 subcutaneous adipose tissue samples were obtained from seven lactating (2nd lactation period) dairy ewes of the Chios breed. Adipose tissue samples were taken from the tail head region at weeks 1, 2, and 4 after weaning (45 days after parturition). Dairy ewes were in negative energy balance during weeks 1 and 2 after weaning and they moved into a strong positive energy balance at week 4 after weaning. Expression of ICDH and G6PD genes and their respective enzymatic activity was determined. Results showed that both genes' expression and enzymatic activities were significantly minimal at week 1 after weaning, reaching a maximum level at week 4 after weaning (P < 0.05). A 3.5-fold and a 5-fold increase of G6PD and ICDH mRNA levels were observed, respectively. Concerning their respective enzymatic activities, a 5.5-fold and 2-fold increase was noted, respectively. A positive correlation was found between ICDH and G6PD gene expression (P < 0.001) indicating a synchronized response to energy intake changes. Almost similar changes were observed for enzymatic activities, rendering these enzymes as potential biochemical markers of ovine lipogenesis.  相似文献   
8.
The ubiquitylation cascade plays an important role in the recruitment of repair factors at DNA double-strand breaks. The involvement of a growing number of ubiquitin E3 ligases adds to the complexity of the DNA damage-induced ubiquitin signaling. Here we use the genetically tractable avian cell line DT40 to investigate the role of HERC2, RNF8 and RNF168 in the DNA damage-induced ubiquitylation pathway. We show that formation of ubiquitin foci as well as cell survival after DNA damage depends on both RNF8 and RNF168. However, we find that RNF8 and RNF168 knockout cell lines respond differently to treatment with camptothecin indicating that they do not function in a strictly linear manner. Surprisingly, we show that HERC2 is required neither for survival nor for ubiquitin foci formation after DNA damage in DT40. Moreover, the E3 ubiquitin ligase activity of HERC2 is not redundant to that of RNF8 or RNF168.  相似文献   
9.
Olive oil history,production and by-product management   总被引:1,自引:0,他引:1  
In this review paper, the history of the olive tree and the development of the main olive oil extraction systems employed in the past are presented. Furthermore, the management techniques employed from antiquity until today for the treatment of olive mill wastewater (OMW), which constitutes the most important by-product of olive oil production, are addressed and compared. Reference is also made to global olive oil production, the environmental impacts of the uncontrolled disposal of OMW, and to the legal framework concerning its management in the main olive oil producing countries. Other by-products of olive processing are also discussed.  相似文献   
10.
We investigated the effect of the physical state of the nutrient medium on the induction of somatic embryogenesis on cell cultures derived from coffee (Coffea arabica L.). Non-embryogenic callus tissues were pulsed initially with 50 μM 6-benzyladenine (BA) for 6, 24 or 48 h in half-strength liquid Murashige and Skoog (MS) medium. After pretreatment, calli were transferred to agar-solidified half-strength MS medium supplemented with 50 μM BA (‘standard induction medium’). Control callus tissues were incubated directly on the solid standard induction medium. Callus growth was promoted by longer pretreatment periods. Formation of globular somatic embryos was observed on callus tissues pretreated with BA for 24 or 48 h, which developed fully to cotyledonary-stage within only 2 weeks after transfer to agar-solidified medium supplemented with BA. No embryo formation occurred in control cultures. Pretreatment with BA in liquid medium was associated with changes in the redox status of cultured cells, such as alterations of the ascorbate–glutathione redox systems and the accumulation of free radicals and oxidized lipids, as well as the possible reduction of cytochrome c-mediated apoptotic pathways. In particular, the induction of somatic embryogenesis was highly positively correlated (r 2 = 0.822) with the accumulation of protein carbonyls. The physiological role of BA as an inducer of both embryonic differentiation and cellular death is discussed.  相似文献   
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