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31.
Exon-intron organization, expression, and chromosomal localization of the human motilin gene 总被引:1,自引:0,他引:1
H Yano Y Seino J Fujita Y Yamada N Inagaki J Takeda G I Bell R L Eddy Y S Fan M G Byers 《FEBS letters》1989,249(2):248-252
The human motilin gene has been isolated and characterized. The gene spans about 9 kilobase pairs (kb) and the 0.7 kb motilin mRNA is encoded by five exons. The 22-amino-acid motilin sequence is encoded by exons 2 and 3. The human motilin gene was mapped to the p21.2----p21.3 region of chromosome 6 by hybridization of the cloned cDNA to DNAs from a panel of reduced human-mouse somatic cell hybrids and by in situ hybridization to human prometaphase chromosomes. RNA blotting using RNA prepared from various regions of the human gastrointestinal tract revealed high levels of motilin mRNA in duodenum and lower levels in the antrum of the stomach; motilin mRNA could not be detected by this procedure in the esophagus, cardia of the stomach, descending colon or gallbladder. 相似文献
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33.
Characterization of the cDNA coding for mouse plasminogen and localization of the gene to mouse chromosome 17 总被引:4,自引:0,他引:4
A full-length cDNA coding for mouse plasminogen has been isolated and characterized. The cDNA is 2720 bp in length (excluding the poly(A) tail) and contains a 24-bp 5' noncoding region, an open reading frame of 2436 bp, and a 3' noncoding region of 257 bp. The open reading frame codes for 812 amino acids and includes a signal peptide that is likely 19 amino acids in length and the mature protein of 793 amino acids. The calculated Mr of mouse plasminogen is 88,706 excluding carbohydrate. There are two potential N-linked carbohydrate addition sites; one of which is glycosylated in human, bovine, and porcine plasminogens. Mouse plasminogen was found to contain two additional amino acids compared to the human protein. In addition, mouse and human plasminogens were found to be 79 and 76% identical at the protein and DNA levels, respectively. Analysis of the segregation of two allelic forms, Plgb and Plgd, of plasminogen DNA in three sets of recombinant inbred strains has allowed the localization of the mouse plasminogen gene to the proximal end of mouse chromosome 17 within the t complex and close to the locus D17Rp17. The Plg gene is deleted in the semidominant deletion mutant, hair-pintail (Thp). 相似文献
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35.
Insulin rapidly induces rat liver S14 gene transcription 总被引:1,自引:0,他引:1
36.
Cloning of cDNAs for human phosphoribosylpyrophosphate synthetases 1 and 2 and X chromosome localization of PRPS1 and PRPS2 genes 总被引:3,自引:0,他引:3
M A Becker S A Heidler G I Bell S Seino M M Le Beau C A Westbrook W Neuman L J Shapiro T K Mohandas B J Roessler 《Genomics》1990,8(3):555-561
Cloned cDNAs representing the entire, homologous (80%) translated sequences of human phosphoribosylpyrophosphate synthetase (PRS) 1 and PRS 2 cDNAs were utilized as probes to localize the corresponding human PRPS1 and PRPS2 genes, previously reported to be X chromosome linked. PRPS1 and PRPS2 loci mapped to the intervals Xq22-q24 and Xp22.2-p22.3, respectively, using a combination of in situ chromosomal hybridization and human x rodent somatic cell panel genomic DNA hybridization analyses. A PRPS1-related gene or pseudogene (PRPS1L2) was also identified using in situ chromosomal hybridization at 9q33-q34. Human HPRT and PRPS1 loci are not closely linked. Despite marked cDNA and deduced amino acid sequence homology, human PRS 1 and PRS 2 isoforms are encoded by genes widely separated on the X chromosome. 相似文献
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38.
Molecular genetic analysis of an FNR-dependent anaerobically inducible Escherichia coli promoter 总被引:13,自引:8,他引:5
From the effects of 13 deletions and three linker-scanner mutations at the Escherichia coli nirB promoter we have located sequences necessary for FNR-dependent induction of activity by anaerobiosis and further nitrite-dependent stimulation of expression. We describe a nirB promoter derivative that allows the cloning of 'cassettes' carrying different FNR-binding sequences and experiments in which a number of point mutations were introduced into these sequences. FNR-dependent stimulation of expression from the nirB promoter is critically dependent on the location of the FNR-binding site, and deletion or insertion of one base pair is sufficient to disrupt promoter function. We have transferred a number of cassette FNR-binding sequences from the nirB promoter to the unrelated melR promoter. The insertion of FNR-binding sequences at the melR promoter is sufficient to confer fnr-dependency on expression. However expression from these hybrid promoters is not as efficiently repressed during aerobic growth, suggesting that the function of bound FNR is dependent on the sequence context of the FNR-binding sequence. 相似文献
39.
Selenocysteine's mechanism of incorporation and evolution revealed in cDNAs of three glutathione peroxidases 总被引:5,自引:0,他引:5
G T Mullenbach A Tabrizi B D Irvine G I Bell J A Tainer R A Hallewell 《Protein engineering》1988,2(3):239-246
The nonsense codon, UGA, has for the first time recently been shown to encode selenocysteine in two proteins, mouse glutathione peroxidase (GSH-Px) (EC 1.11.1.9) and bacterial formate dehydrogenase. A co-translational rather than post-translational selenium-incorporation mechanism has been implicated. Furthermore, high expression levels of GSH-Px have suggested that suppression of termination is efficient and specific. We have isolated and characterized pituitary, kidney and placenta cDNAs for bovine, human and mouse GSH-Px respectively. It is demonstrated that this novel suppression event occurs in diverse tissues, in at least three mammalian species and at the translational step. Surprisingly, GSH-Px is shown to be extramitochondrially encoded, indicating a cytosolic suppression event rather than one utilizing the mitochondria's well-documented extended codon-reading ability. Sequence analysis reveals that a simple proximal contextual pattern responsible for readthrough does not exist. Analysis of predicted secondary structures of mRNAs, however, has revealed a conformation which may be unique to selenocysteine proteins and may prove useful as a tool for artificial incorporation of selenocysteines. A human intron for GSH-Px from an unspliced mRNA has been isolated whose position indicates an ancient, divergent evolutionary relationship with thioredoxin-S2, rather than an independent convergent one. 相似文献
40.