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61.
The ITS1-5.8S-ITS2 sequence region in the Musaceae: structure, diversity and use in molecular phylogeny 总被引:1,自引:0,他引:1
Genes coding for 45S ribosomal RNA are organized in tandem arrays of up to several thousand copies and contain 18S, 5.8S and 26S rRNA units separated by internal transcribed spacers ITS1 and ITS2. While the rRNA units are evolutionary conserved, ITS show high level of interspecific divergence and have been used frequently in genetic diversity and phylogenetic studies. In this work we report on the structure and diversity of the ITS region in 87 representatives of the family Musaceae. We provide the first detailed information on ITS sequence diversity in the genus Musa and describe the presence of more than one type of ITS sequence within individual species. Both Sanger sequencing of amplified ITS regions and whole genome 454 sequencing lead to similar phylogenetic inferences. We show that it is necessary to identify putative pseudogenic ITS sequences, which may have negative effect on phylogenetic reconstruction at lower taxonomic levels. Phylogenetic reconstruction based on ITS sequence showed that the genus Musa is divided into two distinct clades--Callimusa and Australimusa and Eumusa and Rhodochlamys. Most of the intraspecific banana hybrids analyzed contain conserved parental ITS sequences, indicating incomplete concerted evolution of rDNA loci. Independent evolution of parental rDNA in hybrids enables determination of genomic constitution of hybrids using ITS. The observation of only one type of ITS sequence in some of the presumed interspecific hybrid clones warrants further study to confirm their hybrid origin and to unravel processes leading to evolution of their genomes. 相似文献
62.
Liu J Ma H He YL Xie B Xu YF Tang HY Li M Hao W Wang XD Zhang MY Ng CH Goding M Fraser J Herrman H Chiu HF Chan SS Chiu E Yu X 《World psychiatry》2011,10(3):210-216
This paper summarizes the history of the development of Chinese mental health system; the current situation in the mental health field that China has to face in its effort to reform the system, including mental health burden, workforce and resources, as well as structural issues; the process of national mental health service reform, including how it was included into the national public health program, how it began as a training program and then became a treatment and intervention program, its unique training and capacity building model, and its outcomes and impacts; the barriers and challenges of the reform process; future suggestions for policy; and Chinese experiences as response to the international advocacy for the development of mental health. 相似文献
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Edmond Scott 《BMJ (Clinical research ed.)》1951,1(4708):675-677
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Edmond A. D. Boyd 《CMAJ》1965,93(22):1178-1179
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David L. Brautigam Balwant S. Khatra Thomas R. Soderling Edmond H. Fischer 《Archives of biochemistry and biophysics》1982,219(1):228-235
An Mn2+-activated phosphoprotein phosphatase of Mr = 80,000 from rabbit muscle catalyzes the dephosphorylation of skeletal muscle proteins that are phosphorylated by either phosphorylase kinase or cAMP-dependent protein kinase. Phosphorylase or glycogen synthase labeled by phosphorylase kinase at seryl residues 14 or 7, respectively, are both dephosphorylated by the phosphatase. Phosphorylase a and glycogen synthase compete with one another for the phosphatase. The phosphatase discriminates between different sites labeled by the cAMP-dependent protein kinase: glycogen synthase phosphorylated either to 1.0 or 1.8 mol phosphate/mol, or phosphorylase kinase phosphorylated on its β-subunit serve as substrates for the phosphatase, but the phosphorylase kinase α-subunit, the phosphorylated phosphatase inhibitor 1, or casein do not. Histone fraction IIA, phosphorylated by the catalytic subunit, was a poor substrate even at a concentration of 100 μm. Phosphorylation of the α-subunit of phosphorylase kinase had no influence on the kinetics of dephosphorylation of the β-subunit. Thus, the Mr = 80,000 phosphatase meets the functional definition of a protein phosphatase 1 [Cohen, P. (1978) Curr. Top. Cell. Regul.14, 117–196]. Furthermore, from a comparison of the known phosphorylated sites of these proteins, it appears that the phosphatase discriminates between different sites present in the phosphoproteins tested on the basis of the Km values for the reactions. It displays a preferential activity toward proteins with a primary structure wherein basic residues are two positions amino-terminal from the phosphoserine, AgrLysX-YSer(P) or LysArgX-YSer(P), rather and one residue away, ArgArgX-Ser(P). 相似文献
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