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971.
Background
Expression Quantitative Trait Locus (eQTL) mapping methods have been used to identify the genetic basis of gene expression variations. To map eQTL, thousands of expression profiles are related with sequence polymorphisms across the genome through their correlated variations. These eQTL distribute in many chromosomal regions, each of which can include many genes. The large number of mapping results produced makes it difficult to consider simultaneously the relationships between multiple genomic regions and multiple expressional profiles. There is a need for informative bioinformatics tools to assist the visualization and interpretation of these mapping results. 相似文献972.
Pascal Fournier Christian Maizeret David Jimenez Jean-Pierre Chusseau Stéphane Aulagnier François Spitz 《Acta theriologica》2007,52(1):1-12
The European minkMustela lutreola Linnaeus, 1761 and the European polecatMustela putorius Linnaeus, 1758 are related species sympatric in southwestern France. The European mink is rapidly disappearing whereas the
polecat maintains good populations. Seasonal habitat use of both species was compared in the Landes de Gascogne region to
identify if some vulnerability factors of the European mink were associated with habitats occupied by this mustelid. Potential
habitats were mapped using a satellite picture and 12 main types of habitats were defined. Animal locations were recorded
by radiotracking 9 European mink and 14 polecats from March 1996 to August 1999. Resting animals were located by triangulation,
and, when possible, resting places were described. Animals in activity were tracked by continuous monitoring. Data collected
revealed a strong preference of European mink for flooded habitats, particularly open marshes, flooded woodlands and moorlands.
They seldom left the corridor of the riparian forest and their resting places were mainly in flooded environments, above ground
(under herbs or bushes) or in cavities between tree roots. European polecats were less tightly linked to wetlands. Most of
their locations were in the pine forests outside the valleys and their resting places were mainly in burrows. The strong specialisation
of European mink in aquatic habitats is probably one of the main reasons for its decline because wetlands suffer drastic damages
throughout all of its range. Maintaining adequate water levels is crucial for satisfying habitat requirements of mink. 相似文献
973.
Edyta Koscianska Vesselin Baev Konstantinia Skreka Katerina Oikonomaki Ventsislav Rusinov Martin Tabler Kriton Kalantidis 《BMC molecular biology》2007,8(1):79
Background
MicroRNAs (miRNAs) are one of the most abundant groups of regulatory genes in multicellular organisms, playing important roles in many fundamental cellular processes. More than four hundred miRNAs have been identified in humans and the deregulation of miRNA expression has been also shown in many cancers. Despite the postulated involvement of miRNAs in tumourigenesis, there are only a few examples where an oncogene or a tumour suppressor has been identified as a miRNA target. 相似文献974.
975.
976.
977.
Raffaella Di Lisi Anne Picard Simonetta Ausoni Stefano Schiaffino 《BMC molecular biology》2007,8(1):78
Background
We reported previously that the cardiac troponin I (cTnI) promoter drives cardiac-specific expression of reporter genes in cardiac muscle cells and in transgenic mice, and that disruption of GATA elements inactivates the cTnI promoter in cultured cardiomyocytes. We have now examined the role of cTnI promoter GATA elements in skeletal muscle cells. 相似文献978.
Tuberosciponoceras insolitum n. gen., n. sp. is a single dimorphic species in the Upper Albian of the Austrat Basin, southern Patagonia. The short-lived
genus was characterized by distinct ventral tubercles on all ribs and a deep, trifid internal lobe. 相似文献
979.
Cinzia Comino Sergio Lanteri Ezio Portis Alberto Acquadro Annalisa Romani Alain Hehn Romain Larbat Frédéric Bourgaud 《BMC plant biology》2007,7(1):14
Background
Cynara cardunculus L. is an edible plant of pharmaceutical interest, in particular with respect to the polyphenolic content of its leaves. It includes three taxa: globe artichoke, cultivated cardoon, and wild cardoon. The dominating phenolics are the di-caffeoylquinic acids (such as cynarin), which are largely restricted to Cynara species, along with their precursor, chlorogenic acid (CGA). The scope of this study is to better understand CGA synthesis in this plant. 相似文献980.
Balhorn R 《Genome biology》2007,8(9):227
The protamines are a diverse family of small arginine-rich proteins that are synthesized in the late-stage spermatids of many
animals and plants and bind to DNA, condensing the spermatid genome into a genetically inactive state. Vertebrates have from
one to 15 protamine genes per haploid genome, which are clustered together on the same chromosome. Comparison of protamine
gene and amino-acid sequences suggests that the family evolved from specialized histones through protamine-like proteins to
the true protamines. Structural elements present in all true protamines are a series of arginine-rich DNA-anchoring domains
(often containing a mixture of arginine and lysine residues in non-mammalian protamines) and multiple phosphorylation sites.
The two protamines found in mammals, P1 and P2, are the most widely studied. P1 packages sperm DNA in all mammals, whereas
protamine P2 is present only in the sperm of primates, many rodents and a subset of other placental mammals. P2, but not P1,
is synthesized as a precursor that undergoes proteolytic processing after binding to DNA and also binds a zinc atom, the function
of which is not known. P1 and P2 are phosphorylated soon after their synthesis, but after binding to DNA most of the phosphate
groups are removed and cysteine residues are oxidized, forming disulfide bridges that link the protamines together. Both P1
and P2 have been shown to be required for normal sperm function in primates and many rodents. 相似文献