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H. Gonzalo-Turpin P. Barre A. Gibert A. Grisard C. P. West L. Hazard 《Conservation Genetics》2010,11(3):877-887
Choosing the provenance of seed used in ecological restoration could entail its success. An alternative approach to examine local adaptation in seed sourcing is the assessment of genetic structure and diversity based on molecular markers. These types of analyses focus on the genetics of the target plant itself and eliminate the genetic influence of associated organisms, such as Epichloë/Neotyphodium endophytes in grasses. By impacting the fitness of their host, such symbionts may influence population genetic structure and diversity. Therefore, seed sourcing for grasses must consider the influence of their endophytes to increase seed translocation success and minimize the risks associated with this practice. To delineate seed zones for restoration of the alpine fescue Festuca eskia Ramond ex. DC. (Poaceae), we assessed population genetic differentiation and diversity patterns in the species including endophyte occurrence along altitudinal and longitudinal gradients in the Pyrenees Mountains. Twenty-three populations were analysed for endophyte status, and three STS and one SSR marker were used to examine genetic differentiation and diversity patterns. Results showed that F. eskia hosts an asexual form of Epichloë and infection frequency within populations decreased from East to West (100 vs. 8–25%). Molecular markers separated F. eskia into two East and West groups, and endophyte infection and genetic patterns were congruent with molecular data. Little evidence for genetic differentiation or difference in endophyte occurrence associated with altitude was detected. Little variation was found in within population diversity, regardless of provenance altitude and site, and/or endophyte infection frequency. The results of this study suggested the establishment of two distinct management units for F. eskia seed sourcing restoration. 相似文献
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Prenatal maternal psychological distress increases risk for adverse infant outcomes. However, the biological mechanisms underlying this association remain unclear. Prenatal stress can impact fetal epigenetic regulation that could underlie changes in infant stress responses. It has been suggested that maternal glucocorticoids may mediate this epigenetic effect. We examined this hypothesis by determining the impact of maternal cortisol and depressive symptoms during pregnancy on infant NR3C1 and BDNF DNA methylation. Fifty-seven pregnant women were recruited during the second or third trimester. Participants self-reported depressive symptoms and salivary cortisol samples were collected diurnally and in response to a stressor. Buccal swabs for DNA extraction and DNA methylation analysis were collected from each infant at 2 months of age, and mothers were assessed for postnatal depressive symptoms. Prenatal depressive symptoms significantly predicted increased NR3C1 1F DNA methylation in male infants (β = 2.147, P = 0.044). Prenatal depressive symptoms also significantly predicted decreased BDNF IV DNA methylation in both male and female infants (β = −3.244, P = 0.013). No measure of maternal cortisol during pregnancy predicted infant NR3C1 1F or BDNF promoter IV DNA methylation. Our findings highlight the susceptibility of males to changes in NR3C1 DNA methylation and present novel evidence for altered BDNF IV DNA methylation in response to maternal depression during pregnancy. The lack of association between maternal cortisol and infant DNA methylation suggests that effects of maternal depression may not be mediated directly by glucocorticoids. Future studies should consider other potential mediating mechanisms in the link between maternal mood and infant outcomes. 相似文献
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M. Montenegro C. Cardenas C. Cuervo C. Bernal E. C. Grisard M. C. Thomas M. C. Lopez C. J. Puerta 《Molecular biology reports》2013,40(8):4901-4912
Calcineurin B, the regulatory subunit of calcineurin, a serine/threonine protein phosphatase, is highly conserved throughout the evolutionary scale including trypanosomatids such as Trypanosoma cruzi, and Leishmania major. Thus, in these flagellates the protein is required for mammalian host cell invasion and virulence and stress responses. With the aim of determining the presence of calcineurin B in Trypanosoma rangeli, a non-virulent trypanosome for mammals, the respective gene was amplified by PCR, cloned and sequenced. Two sequences of 531 bp in length showing a nucleotide polymorphism (314A>C) were obtained in spite of a single-copy gene was revealed by Southern blot. These sequences, probably the alleles from the gene, showed a 79 % of identity with those from T. cruzi and clustered as the sister group of this trypanosome species in a Maximum Parsimony analysis. Deduced amino acid sequence comparison with trypanosomatids and other organisms through the phylogenetic scale as well as the obtained protein structural homology model suggested the presence of the four potential EF-hand regions and the corresponding calcium binding sites of the last three of these domains. Having assessed the expression of this protein in T. rangeli epimastigotes, and taking into account the following facts: (i) calcineurin inhibitors have inhibitory effect on the in vitro replication of T. cruzi, (ii) L. major promastigote growth is inhibited by chelating agents, and (iii) T. rangeli does not seem to productively infect mammalian cells, it is hypothesized herein that the function of this protein in T. rangeli is required for epimastigote growth. 相似文献
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Determination of HLA antigens can be used for prenatal diagnosis of some congenital anomalies such as adrenal hyperplasia (21-hydroxylase deficiency). This necessitates rigourous HLA typing of fetal cells cultivated in vitro. The method we have developed utilizes microcytotoxicity and quantitative microabsorption tests which have been adapted to the types of cells found in these cultures. 相似文献