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111.
Structural diversity and evolution of human receptor-like protein tyrosine phosphatases. 总被引:59,自引:8,他引:51 下载免费PDF全文
Protein tyrosine phosphatases (PTPases), together with protein tyrosine kinases, regulate the tyrosine phosphorylation that controls cell activities and proliferation. Previously, it has been recognized that both cytosolic PTPases and membrane associated, receptor-like PTPases exist. In order to examine the structural diversity of receptor-like PTPases, we isolated human cDNA clones that cross-hybridized to a Drosophila PTPase cDNA clone, DPTP12, under non-stringent hybridization conditions. The cDNA clones thus isolated included LCA and six other novel receptor-like PTPases, named HPTP alpha, beta, gamma, delta, epsilon, and zeta. The cytoplasmic regions of HPTP alpha and epsilon are highly homologous, and are composed of two tandemly duplicated PTPase-like domains. The extracellular regions of HPTP alpha and epsilon are, respectively, 123 amino acids and 27 amino acids, and do not have obvious similarity to any known protein. The cytoplasmic region of HPTP beta contains only one PTPase domain. The extracellular region of HPTP beta, which is 1599 amino acids, is composed of 16 fibronectin type-III repeats. HPTP delta is very similar to leukocyte common antigen related molecule (LAR), in both the extracellular and cytoplasmic regions. Partial sequences of HPTP gamma and zeta indicate that they are highly homologous and contain two PTPase-like domains. The PTPase-like domains of HPTP alpha, beta and delta expressed in Escherichia coli had tyrosine phosphatase activities. 相似文献
112.
Growth and development of biofeedback: A bibliographic update 总被引:1,自引:0,他引:1
Computerized literature searching techniques were used to examine publication patterns in the worldwide biofeedback literature. Searches were completed in the United States and in Japan for the years 1985 through 1987. The results were used to update the results of an earlier study (Hatch & Riley, 1985) that covered the years from 1964 through 1984. Publication growth curves were generated for several media, including scientific journal articles, books, doctoral dissertations, and popular magazine articles. Although publication of information about biofeedback remains active worldwide, there has been a declining trend in effect for the past several years. The American database grossly underestimated the number of Japanese biofeedback articles, and it is likely that the literatures of other countries outside of North America were similarly underestimated. Possible explanations for the various trends noted are discussed.These results were presented in part at the Twentieth Annual Meeting of the Association for Applied Psychophysiology and Biofeedback. We gratefully acknowledge the assistance of Margaret Cyr-Provost in preparing the data for analysis. 相似文献
113.
Ochiai Hiroshi; Hata Katsusuke; Saito Tamao; Funamoto Satoru; Nakata Nobuyuki 《Plant & cell physiology》1996,37(2):135-139
The cellular slime mold, Polysphondylium pallidum, has two EDTA-resistanttypes of cell-cell adhesion. The major component of them hasbeen identified as a glycoprotein with a molecular mass of 64kDa on SDS-PAGE (referred to as gp64). We found that a substantialamount of the gp64 run as dimer, when gp64 was dissolved inSDS-sample buffer without 2-mercaptoethanol and then subjectedto electrophoresis. The occurrence of a homophilic dimer wasdemonstrated by analyzing the dimer-like band on a gel for itsamino acid sequence and amino acid composition. The dimer-likeband also was analyzed by three sorts of monoclonal antibodies,two of which recognize respectively a conforniational epitopeand a denatured epitope of the protein moiety of gp64. The dataindicate that the native conformation of gp64 is necessary fordimer formation.
2Present address: Institute of Immunological Science, HokkaidoUniversity, Sapporo, 060 Japan 相似文献
114.
Estimation of the position and effect of a lethal factor locus on a molecular marker linkage map 总被引:3,自引:0,他引:3
R. Cheng A. Saito Y. Takano Y. Ukai 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,93(4):494-502
In the mapping of DNA markers the distortion of segregation of marker genotypes is often observed, which may be caused by a lethal factor acting in filial generations derived from distant crosses. A method is presented for estimating the recombination values between a lethal factor locus and neighboring molecular markers, and the relative viability or fertilization ability of gametes or zygotes affected by the lethal factor in an F2 population using the maximum likelihood method and the expectation conditional maximization (ECM) algorithm. Three selection models of gamete or zygote were considered, and the most likely one was determined by goodness of fit of the observed frequency of the phenotypes to the expected ones under the models. The method was applied to segregation data of molecular markers of an F2 population consisting of 144 individuals derived from a cross between an Indica and a Japonica rice variety. The presence of a lethal factor locus (L) located on chromosome III that caused partial gametic selection in both the male and female sides was suggested. The locus L was tightly linked to RFLP marker number 23 of the RFLP linkage map of Saito et al. (1991a), and the fertilization chance of a male or female gamete possessing the lethal factor was, on average, 41.5% of that of the normal gamete. 相似文献
115.
Tohru Tsukui Sanae Miyake Sadahiro Azuma Hirotake Ichise Izumu Saito Yutaka Toyoda 《Molecular reproduction and development》1995,42(3):291-297
Replication-defective recombinant adenovirus, Adex4SRLacZL, was used as a vector for transferring exogenous genes in mouse zona pellucida-free eggs at the pronuclear stage. The vector contained the E. coli LacZ reporter gene under the control of the SRα promoter (SV40 early promoter-fused HTLV-I LTR), and the expression of the reporter gene was examined during preimplantation development in culture. Histochemical staining of the embryos for β-galactosidase activity showed that the exogenous LacZ gene as expressed in 98% of the embryos at the morula-blastocyst stages. As in the microinjection method, the exogenous genes could be pursued from the 2-cell stage. Neither apparent morphological changes nor cytotoxic effects were observed. Both the percentages of embryos expressing reporter genes and the rate of development to the blastocyst stage were higher in the adenovirus vector-treated embryos than in the microinjected ones. These results suggest that the adenovirus vector system is a useful tool in investigating the genetic control of early mammalian development. © 1995 wiley-Liss, Inc. 相似文献
116.
Katsumi Mominoki Noriko Nakagawa-Tosa Masami Morimatsu Bunei Syuto Masayuki Saito 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1995,110(4):785-789
Haptoglobin (Hp), a hemoglobin-binding protein in plasma, consists of α and β subunits and has a tetra-chain arrangement (β-α-α-β) connected by disulfide bridges in most mammals so far examined. Dog Hp has been reported to be unique compared with other Hps in respect that (1) the two αβ units are joined by a non-covalent interaction rather than a disulfide bridge and (2) the α chain has an oligosaccharide-binding sequence (Asn-X-Ser/Thr) and is glycosylated. To determine whether the unique structures of dog Hp are common in the Carnivora, we purified Hps from sera of bear and cat, and analyzed their subunit structure and partial amino acid sequences. The analyses by gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, under both reducing and non-reducing conditions, revealed that bear and cat Hps have similar subunit arrangements to dog Hp, suggesting the absence of a disulfide bridge between two α chains. This was confirmed by amino acid sequence analysis of the α chains: that is, Cys15 participating in the inter-α chain disulfide bridge was replaced by Val in bear or Leu in cat and dog. Thus, the unique subunit arrangement of Hp reported in dog may be common in the Carnivora. In contrast to dog Hp, however, α chains of bear and cat Hps were found not to have the typical oligosaccharide binding sequence on their α chains and were not glycosylated. 相似文献
117.
118.
Satoru Kobayashi Hiromitsu Saito Masukichi Okada 《Development, growth & differentiation》1994,36(6):629-632
We report a simplified and reliable method for non-radioactive in situ hybridization to whole Drosophila embryos. In the previous method (Tautz and Pfeifle, 1989) the post-hybridization wash, or the procedure for washing non-hybridized probe away from embryos depends simply on diffusion. We modified the method with application of electrophoresis to the wash. After hybridized with RNA probe, embryos were transferred to a small well where an electric charge was given to drive non-hybridized probe away from the embryos. This procedure enables us to acquire a much higher signal-to-noise ratio than that obtained from a conventional method. Furthermore, this is a time-saving method. We propose a term "electro-wash" for this procedure. 相似文献
119.
Identification of the duplicated segments in rice chromosomes 1 and 5 by linkage analysis of cDNA markers of known functions 总被引:9,自引:0,他引:9
N. Kishimoto H. Higo K. Abe S. Arai A. Saito K. Higo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,88(6-7):722-726
We mapped two loci for ADP-ribosylation factor homologues (ARF1, ARF2) and two loci for cysteine proteinase inhibitors (oryzacystatin-I and -II: OCI, OCII) by linkage analysis of restriction fragment length polymorphism loci in rice (Oryza sativa L.) genomic DNAs using their cDNAs as probes.Oc-1 andArf-2 were found to be closely located to each other on chromosome 1, whileOc-2 andArf-1,both found on chromosome 5, were also located close to each other. The map distances are about 2 cM in both pairs. In each chromosome, theArf locus was located about 27 cM from that of the aldolase gene (Ald-2 in chromosome 1 andAld-1 in chromosome 5). These three genes are in the same order,Ald-Arf-Oc, but in opposite orientations relative to the distal ends of the linkage group. The presence of two sets of three linked genes on chromosomes 1 and 5 strongly suggests a structural similarity of the blocks of the two chromosomes, which probably reflects duplication of the segment. A recent investigation by other workers has shown that these rice blocks correspond to two regions in maize chromosomes 8 and 6, that have previously been shown to share many duplicated nucleotide sequences. It is therefore very likely that the duplication of the region occurred before the divergence of rice and maize during the evolution of the subfamilies of the grasses (Gramineae). In view of a recently discovered possible structural similarity between the small GTP-binding protein superfamily, which includesArf andras proteins, and the cystatin family, the close linkage ofOc andArf loci found in the present study suggests a possible cluster of genes related to the small GTP-binding proteins. 相似文献
120.
N. Ikeda Y. Saito J. Shimizu A. Ochi J. Mizutani J. Watabe 《Journal of applied microbiology》1994,77(2):185-194
Variations between and within individuals, and correlations between concentrations of bacterial metabolites, including putrefactive products, ammonia and short chain fatty acids (SCFAs), enzyme activities, moisture and pH, as well as bacterial composition, were studied in faecal samples from seven healthy adults over a period of 7 months. Large variations, both between and within individuals, were observed in concentrations of putrefactive products. Although values for ammonia, SCFAs, enzyme activities, moisture and pH were generally variable, significant person-to-person differences were observed.
While ranges of log viable counts of the predominant bacteria such as eubacteria, bifidobacteria and bacteroides in each subject remained between 0·2 and 1·3, those of enterobacteria, streptococci (including enterococci) and lecithinase-negative clostridia varied between 0·4 and 3·0. Levels of bifidobacteria, enterobacteria, streptococci and total aerobic bacteria showed inter-individual variations. Correlations were found among certain of the parameters: moisture correlated negatively with p -cresol ( r = -0·707), pH ( r = -0–671) and β-glucosidase activity (GS) ( r = -0·608), and positively with acetic acid ( r = 0·621), while negative correlations were observed in pH with acetic and butyric acids ( r = -0·690 and -0·623, respectively).
No significant correlations were found between bacterial compositions, and other faecal factors such as pH, moisture, metabolic enzyme activities and concentrations of putrefactive products. 相似文献
While ranges of log viable counts of the predominant bacteria such as eubacteria, bifidobacteria and bacteroides in each subject remained between 0·2 and 1·3, those of enterobacteria, streptococci (including enterococci) and lecithinase-negative clostridia varied between 0·4 and 3·0. Levels of bifidobacteria, enterobacteria, streptococci and total aerobic bacteria showed inter-individual variations. Correlations were found among certain of the parameters: moisture correlated negatively with p -cresol ( r = -0·707), pH ( r = -0–671) and β-glucosidase activity (GS) ( r = -0·608), and positively with acetic acid ( r = 0·621), while negative correlations were observed in pH with acetic and butyric acids ( r = -0·690 and -0·623, respectively).
No significant correlations were found between bacterial compositions, and other faecal factors such as pH, moisture, metabolic enzyme activities and concentrations of putrefactive products. 相似文献