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331.
Sena Karachanak Viola Grugni Simona Fornarino Desislava Nesheva Nadia Al-Zahery Vincenza Battaglia Valeria Carossa Yordan Yordanov Antonio Torroni Angel S. Galabov Draga Toncheva Ornella Semino 《PloS one》2013,8(3)
To better define the structure and origin of the Bulgarian paternal gene pool, we have examined the Y-chromosome variation in 808 Bulgarian males. The analysis was performed by high-resolution genotyping of biallelic markers and by analyzing the STR variation within the most informative haplogroups. We found that the Y-chromosome gene pool in modern Bulgarians is primarily represented by Western Eurasian haplogroups with ∼ 40% belonging to haplogroups E-V13 and I-M423, and 20% to R-M17. Haplogroups common in the Middle East (J and G) and in South Western Asia (R-L23*) occur at frequencies of 19% and 5%, respectively. Haplogroups C, N and Q, distinctive for Altaic and Central Asian Turkic-speaking populations, occur at the negligible frequency of only 1.5%. Principal Component analyses group Bulgarians with European populations, apart from Central Asian Turkic-speaking groups and South Western Asia populations. Within the country, the genetic variation is structured in Western, Central and Eastern Bulgaria indicating that the Balkan Mountains have been permeable to human movements. The lineage analysis provided the following interesting results: (i) R-L23* is present in Eastern Bulgaria since the post glacial period; (ii) haplogroup E-V13 has a Mesolithic age in Bulgaria from where it expanded after the arrival of farming; (iii) haplogroup J-M241 probably reflects the Neolithic westward expansion of farmers from the earliest sites along the Black Sea. On the whole, in light of the most recent historical studies, which indicate a substantial proto-Bulgarian input to the contemporary Bulgarian people, our data suggest that a common paternal ancestry between the proto-Bulgarians and the Altaic and Central Asian Turkic-speaking populations either did not exist or was negligible. 相似文献
332.
Franzese Ornella Minotti Linda Aguiari Gianluca Corrà Fabio Cervellati Carlo Ferrari Carlo Volinia Stefano Bergamini Carlo M. Bianchi Nicoletta 《Amino acids》2019,51(9):1273-1288
Amino Acids - The multifunctional protein Transglutaminase type 2, is associated with cancer epithelial mesenchymal transition, invasiveness, stemness and drugs resistance. Several variant isoforms... 相似文献
333.
Calcium influx and mitochondrial alterations at synapses exposed to snake neurotoxins or their phospholipid hydrolysis products 总被引:1,自引:0,他引:1
Rigoni M Pizzo P Schiavo G Weston AE Zatti G Caccin P Rossetto O Pozzan T Montecucco C 《The Journal of biological chemistry》2007,282(15):11238-11245
Snake presynaptic phospholipase A2 neurotoxins (SPANs) bind to the presynaptic membrane and hydrolyze phosphatidylcholine with generation of lysophosphatidylcholine (LysoPC) and fatty acid (FA). The LysoPC+FA mixture promotes membrane fusion, inducing the exocytosis of the ready-to-release synaptic vesicles. However, also the reserve pool of synaptic vesicles disappears from nerve terminals intoxicated with SPAN or LysoPC+FA. Here, we show that LysoPC+FA and SPANs cause a large influx of extracellular calcium into swollen nerve terminals, which accounts for the extensive synaptic vesicle release. This is paralleled by the change of morphology and the collapse of membrane potential of mitochondria within nerve bulges. These results complete the picture of events occurring at nerve terminals intoxicated by SPANs and define the LysoPC+FA lipid mixture as a novel and effective agonist of synaptic vesicle release. 相似文献
334.
The loss of telomerase activity in highly differentiated CD8+CD28-CD27- T cells is associated with decreased Akt (Ser473) phosphorylation 总被引:2,自引:0,他引:2
335.
Belkis E. Marelli Cristian J.M. Leiva Rocío B. Flores Brun Cintia S. Ramírez Juan I. Failla Valentina Matiller Ayelén N. Amweg Florencia Rey Hugo H. Ortega 《Reproductive biology》2018,18(4):432-439
In ovarian granulosa cells, follicle-stimulating hormone (FSH) regulates the proliferation and differentiation events required for follicular growth and oocyte maturation. FSH actions are mediated exclusively through the FSH receptor (FSHR). In cattle, the FSHR gene expression pattern during folliculogenesis and the implications of this receptor in reproductive disorders have been extensively studied. However, the limited availability of specific antibodies against bovine FSHR has restricted FSHR protein analysis. In the present study, we developed an anti-FSHR polyclonal serum by using a 14-kDa peptide conjugated to maltose binding protein. The antiserum obtained was characterized by western blot of protein extracts from bovine follicles, BGC-1 cells and primary cultures of granulosa cells stimulated with testosterone. Also, the blocking effect of serum on estradiol secretion and cell viability after gonadotropin stimulus was characterized in a functional in vitro assay. A 76-kDa protein, consistent with the predicted molecular size of full-length FSHR, was detected in ovarian tissue. Besides, two immunoreactive bands of 60-kDa and 30-kDa (only in cultured cells) were detected. These bands would be related to some of the isoforms of the receptor. Therefore, immunohistochemical assays allowed detecting FSHR in the cytoplasm of granulosa cells and an increase in its expression as follicles progressed from primordial to large preantral follicles. These results suggest that the anti-FSHR serum here developed has good reactivity and specificity against the native FSHR. Therefore, this antiserum may serve as a valuable tool for future studies of the biological function of FSHR in physiological conditions as well as of the molecular mechanism and functional involvement of FSHR in reproductive disorders. 相似文献
336.
Cultured fibroblasts adhere to extracellular substrates by means of cell-matrix adhesions that are assembled in a hierarchical way, thereby gaining in protein complexity and size. Here we asked how restricting the size of cell-matrix adhesions affects cell morphology and behavior. Using a nanostencil technique, culture substrates were patterned with gold squares of a width and spacing between 250 nm and 2 μm. The gold was functionalized with RGD peptide as ligand for cellular integrins, and mouse embryo fibroblasts were plated. Limiting the length of cell-matrix adhesions to 500 nm or less disturbed the maturation of vinculin-positive focal complexes into focal contacts and fibrillar adhesions, as indicated by poor recruitment of α5-integrin. We found that on sub-micrometer patterns, fibroblasts spread extensively, but did not polarize. Instead, they formed excessive numbers of lamellipodia and a fine actin meshwork without stress fibers. Moreover, these cells showed aberrant fibronectin fibrillogenesis, and their speed of directed migration was reduced significantly compared to fibroblasts on 2 μm square patterns. Interference with RhoA/ROCK signaling eliminated the pattern-dependent differences in cell morphology. Our results indicate that manipulating the maturation of cell-matrix adhesions by nanopatterned surfaces allows to influence morphology, actin dynamics, migration and ECM assembly of adhering fibroblasts. 相似文献
337.
An urokinase receptor antagonist that inhibits cell migration by blocking the formyl peptide receptor 总被引:1,自引:0,他引:1
Bifulco K Longanesi-Cattani I Gargiulo L Maglio O Cataldi M De Rosa M Stoppelli MP Pavone V Carriero MV 《FEBS letters》2008,582(7):1141-1146
Urokinase receptor (uPAR) plays a key role in physiological and pathological processes sustained by an altered cell migration. We have developed peptides carrying amino acid substitutions along the Ser(88)-Arg-Ser-Arg-Tyr(92) (SRSRY) uPAR chemotactic sequence. The peptide pyro glutamic acid (pGlu)-Arg-Glu-Arg-Tyr-NH2 (pERERY-NH(2)) shares the same binding site with SRSRY and competes with N-formyl-Met-Leu-Phe (fMLF) for binding to the G-protein-coupled N-formyl-peptide receptor (FPR). pERERY-NH(2) is a dose-dependent inhibitor of both SRSRY- and fMLF-directed cell migration, and prevents agonist-induced FPR internalization and fMLF-dependent ERK1/2 phosphorylation. pERERY-NH(2) is a new and potent uPAR inhibitor which may suggest the generation of new pharmacological treatments for pathological conditions involving increased cell migration. 相似文献
338.
339.
The genome sequence of the most widely cultivated cacao type and its use to identify candidate genes regulating pod color 总被引:1,自引:0,他引:1
Juan C Motamayor Keithanne Mockaitis Jeremy Schmutz Niina Haiminen Donald Livingstone III Omar Cornejo Seth D Findley Ping Zheng Filippo Utro Stefan Royaert Christopher Saski Jerry Jenkins Ram Podicheti Meixia Zhao Brian E Scheffler Joseph C Stack Frank A Feltus Guiliana M Mustiga Freddy Amores Wilbert Phillips Jean Philippe Marelli Gregory D May Howard Shapiro Jianxin Ma Carlos D Bustamante Raymond J Schnell Dorrie Main Don Gilbert Laxmi Parida David N Kuhn 《Genome biology》2013,14(6):r53
340.
Where west meets east: the complex mtDNA landscape of the southwest and Central Asian corridor 总被引:21,自引:0,他引:21 下载免费PDF全文
Quintana-Murci L Chaix R Wells RS Behar DM Sayar H Scozzari R Rengo C Al-Zahery N Semino O Santachiara-Benerecetti AS Coppa A Ayub Q Mohyuddin A Tyler-Smith C Qasim Mehdi S Torroni A McElreavey K 《American journal of human genetics》2004,74(5):827-845
The southwestern and Central Asian corridor has played a pivotal role in the history of humankind, witnessing numerous waves of migration of different peoples at different times. To evaluate the effects of these population movements on the current genetic landscape of the Iranian plateau, the Indus Valley, and Central Asia, we have analyzed 910 mitochondrial DNAs (mtDNAs) from 23 populations of the region. This study has allowed a refinement of the phylogenetic relationships of some lineages and the identification of new haplogroups in the southwestern and Central Asian mtDNA tree. Both lineage geographical distribution and spatial analysis of molecular variance showed that populations located west of the Indus Valley mainly harbor mtDNAs of western Eurasian origin, whereas those inhabiting the Indo-Gangetic region and Central Asia present substantial proportions of lineages that can be allocated to three different genetic components of western Eurasian, eastern Eurasian, and south Asian origin. In addition to the overall composite picture of lineage clusters of different origin, we observed a number of deep-rooting lineages, whose relative clustering and coalescent ages suggest an autochthonous origin in the southwestern Asian corridor during the Pleistocene. The comparison with Y-chromosome data revealed a highly complex genetic and demographic history of the region, which includes sexually asymmetrical mating patterns, founder effects, and female-specific traces of the East African slave trade. 相似文献