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91.
Diego Micheletti Maria Teresa Dettori Sabrina Micali Valeria Aramini Igor Pacheco Cassia Da Silva Linge Stefano Foschi Elisa Banchi Teresa Barreneche Bénédicte Quilot-Turion Patrick Lambert Thierry Pascal Ignasi Iglesias Joaquim Carbó Li-rong Wang Rui-juan Ma Xiong-wei Li Zhong-shan Gao Nelson Nazzicari Michela Troggio Daniele Bassi Laura Rossini Ignazio Verde Fran?ois Laurens Pere Arús Maria José Aranzana 《PloS one》2015,10(9)
Peach was domesticated in China more than four millennia ago and from there it spread world-wide. Since the middle of the last century, peach breeding programs have been very dynamic generating hundreds of new commercial varieties, however, in most cases such varieties derive from a limited collection of parental lines (founders). This is one reason for the observed low levels of variability of the commercial gene pool, implying that knowledge of the extent and distribution of genetic variability in peach is critical to allow the choice of adequate parents to confer enhanced productivity, adaptation and quality to improved varieties. With this aim we genotyped 1,580 peach accessions (including a few closely related Prunus species) maintained and phenotyped in five germplasm collections (four European and one Chinese) with the International Peach SNP Consortium 9K SNP peach array. The study of population structure revealed the subdivision of the panel in three main populations, one mainly made up of Occidental varieties from breeding programs (POP1OCB), one of Occidental landraces (POP2OCT) and the third of Oriental accessions (POP3OR). Analysis of linkage disequilibrium (LD) identified differential patterns of genome-wide LD blocks in each of the populations. Phenotypic data for seven monogenic traits were integrated in a genome-wide association study (GWAS). The significantly associated SNPs were always in the regions predicted by linkage analysis, forming haplotypes of markers. These diagnostic haplotypes could be used for marker-assisted selection (MAS) in modern breeding programs. 相似文献
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Magda Gioia Giovanni Francesco Fasciglione Susanna Monaco Riccardo Iundusi Diego Sbardella Stefano Marini Umberto Tarantino Massimo Coletta 《Journal of biological inorganic chemistry》2010,15(8):1219-1232
The proteolytic processing of collagen I by three matrix metalloproteinases (MMPs), a collagenase (MMP-1), a gelatinase (MMP-2),
and the ectodomain of a membrane-type metalloproteinase (MMP-14), has been investigated at 37 °C between pH 6.0 and 9.2, a
pH range reflecting conditions found in different body compartments under various physiopathological processes. In the proteolytic
degradation the native collagen triple helix must be partially unwound to allow the binding of α chains to the protease’s
active-site cleft. We have found that MMP-1 interacts with the two types of collagen I α chains in a similar fashion, whereas
both MMP-2 and MMP-14 bind the two α chains in a different way. The overall enzymatic activity is higher on the α-2 chain
for both MMP-1 and MMP-2, whereas the MMP-14 ectodomain preferentially cleaves the α-1 chain. In MMP-2 a marked difference
for substrate affinity (higher for the α-1 chain) is overwhelmed by an even more marked propensity to cleave the α-2 chain.
As a whole, the three classes of MMPs investigated appear to process collagen I in a significantly different fashion, so various
MMPs play different roles in the collagen homeostasis in various compartments (such as bloodstream, synovial fluid, normal
and tumoral tissues), where different pH values are observed. 相似文献
94.
A new species of Ctenomyidae from the late Pliocene of Uquía Formation (northwestern Argentina) is described. The new remains consist of a fragmentary rostrum, and a left mandible with partial lower dentition. Its phylogenetic affinity and morphological specializations for tooth-digging support its assignation to the South American rodent genus Ctenomys. In this context, we highlight the importance of unique morphological specializations for the delimitation of genera within an intrafamilial clade in which similar adaptive strategies could have evolved more than once. The new materials are the oldest fossils for the genus (ca. 3.5 Ma), and their finding in the central Andes agrees with previous hypotheses about the possible area of origin of Ctenomys. They precede by about one million years the presence of Ctenomys chapalmalensis in the Pliocene of the Pampean region of central Argentina, the oldest record previously known for the genus. Nevertheless, the new species does not contribute key information about ancestral character states for the genus beyond those already known through C. chapalmalensis. The phylogenetic, adaptive and even chronological information supplied by these new materials would be linked to the differentiation of the genus rather than to its origin. 相似文献
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Philippe Lehert Joan C Schertz Diego Ezcurra 《Reproductive biology and endocrinology : RB&E》2010,8(1):112