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Considerable Homology (considerable + homology)
Selected AbstractsCloning, chromosomal localization and characterization of the murine mucin gene orthologous to human MUC4FEBS JOURNAL, Issue 13 2002Jean-Luc Desseyn We report here the full coding sequence of a novel mouse putative membrane-associated mucin containing three extracellular EGF-like motifs and a mucin-like domain consisting of at least 20 tandem repeats of 124,126 amino acids. Screening a cosmid and a BAC libraries allowed to isolate several genomic clones. Genomic and cDNA sequence comparisons showed that the gene consists of 25 exons and 24 introns covering a genomic region of ,,52 kb. The first intron is ,,16 kb in length and is followed by an unusually large exon (, 9.5 kb) encoding Ser/Thr-rich tandemly repeated sequences. Radiation hybrid mapping localized this new gene to a mouse region of chromosome 16, which is the orthologous region of human chromosome 3q29 encompassing the large membrane-anchored mucin MUC4. Contigs analysis of the Human Genome Project did not reveal any other mucin on chromosome 3q29 and, interestingly, our analysis allowed the determination of the genomic organization of the human MUC4 and showed that its exon/intron structure is identical to that of the mouse gene we cloned. Furthermore, the human MUC4 shares considerable homologies with the mouse gene. Based on these data, we concluded that we isolated the mouse ortholog of MUC4 we propose as Muc4. Expression studies showed that Muc4 is ubiquitous like SMC and MUC4, with highest levels of expression in trachea and intestinal tract. [source] Expression survey of genes critical for tooth development in the human embryonic tooth germDEVELOPMENTAL DYNAMICS, Issue 5 2007Dahe Lin Abstract In the developing murine tooth, the expression patterns of numerous regulatory genes have been examined and their roles have begun to be revealed. To unveil the molecular mechanisms that regulate human tooth morphogenesis, we examined the expression patterns of several regulatory genes, including BMP4, FGF8, MSX1, PAX9, PITX2, and SHOX2, and compared them with that found in mice. All of these genes are known to play critical roles in murine tooth development. Our results show that these genes exhibit basically similar expression patterns in the human tooth germ compared with that in the mouse. However, slightly different expression patterns were also observed for some of the genes at certain stages. For example, MSX1 expression was detected in the inner enamel epithelium in addition to the dental mesenchyme at the bell stage of the human tooth. Moreover, FGF8 expression remained in the dental epithelium at the cap stage, while PAX9 and SHOX2 expression was detected in both dental epithelium and mesenchyme of the human tooth germ. Our results indicate that, although slight differences exist in the gene expression patterns, the human and mouse teeth not only share considerable homology in odontogenesis but also use similar underlying molecular networks. Developmental Dynamics 236:1307,1312, 2007. © 2007 Wiley-Liss, Inc. [source] Characterization of the Coat Protein Gene of Cymbidium mosaic virus Isolates from IndiaJOURNAL OF PHYTOPATHOLOGY, Issue 5 2006A. R. Sherpa Abstract The variability in the coat protein (CP) gene sequence of Cymbidium mosaic virus (CymMV) that naturally infects orchids worldwide was investigated. Samples were collected from different regions of India, and the gene encoding the CP of nine isolates was specifically amplified by reverse-transcription polymerase chain reaction. The amplified product obtained was cloned, sequenced and multiple sequence alignment of deduced amino acid (aa) sequences revealed considerable homology to CymMV isolates from other countries. The nucleotide sequences and the amino acid sequences were found to be 85,100% identical and 65,100% respectively. Such high sequence conservation suggests that the CymMV CP gene is highly conserved and is a suitable candidate for the development of diagnostic procedures and to provide transgenic resistance to orchids cultivated in different geographical locations. Although recombination is not common among CymMV isolates, one isolate from Cymbidium was found to be a recombinant between a Korean and a Thai isolate of the virus. IHBT communication no: 0451. [source] Serine/threonine kinase PKR: A sentinel kinase that discriminates a signaling pathway mediated by TLR4 from those mediated by TLR3 and TLR9AMERICAN JOURNAL OF HEMATOLOGY, Issue 7 2007Yusuke Asakura Abstract Cells of the innate immune system discriminate between "noninfectious self" and "infectious nonself" via pattern recognition receptors known as Toll-like receptors (TLRs). Though TLRs and the related interleukin 1 receptors share considerable homology in their cytoplasmic domains and adaptor molecules, signaling cascades may substantially differ from one another depending on the adaptor proteins recruited. Here we show that ectopic overexpression of catalytically inactive dominant-negative PKR expression system suppressed NF- , B activation mediated by TLR3, TLR9, TNF receptor 1 and 2 (TNF-R 1/2), but not by TLR4. Physiological relevance of the observations described here are discussed. Am. J. Hematol 2007. © 2006 Wiley-Liss, Inc. [source] | ||||||||||