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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995.
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
996.
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997.
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
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Background
The need for discovery of alternative, renewable, environmentally friendly energy sources and the development of cost-efficient, "clean" methods for their conversion into higher fuels becomes imperative. Ethanol, whose significance as fuel has dramatically increased in the last decade, can be produced from hexoses and pentoses through microbial fermentation. Importantly, plant biomass, if appropriately and effectively decomposed, is a potential inexpensive and highly renewable source of the hexose and pentose mixture. Recently, the engineered (to also catabolize pentoses) anaerobic bacterium Zymomonas mobilis has been widely discussed among the most promising microorganisms for the microbial production of ethanol fuel. However, Z. mobilis genome having been fully sequenced in 2005, there is still a small number of published studies of its in vivo physiology and limited use of the metabolic engineering experimental and computational toolboxes to understand its metabolic pathway interconnectivity and regulation towards the optimization of its hexose and pentose fermentation into ethanol. 相似文献1000.
Debra L Fisk Leigh C LattaIV Roland A Knapp Michael E Pfrender 《BMC evolutionary biology》2007,7(1):22