Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.1.28 (chloramphenicol acetyltransferase)
 5,100 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Chromogranin A (CgA) is an acidic glycoprotein, which is widely expressed in endocrine and neuroendocrine cells. It plays multiple important roles in the process of regulated hormone secretion. The single copy human CgA gene was isolated from a human fetal liver gene library. The gene spans 15 kilobases and contains 8 exons. Exon I encodes the 5'-noncoding region and the majority of the signal peptide coding region. Exons II-V collectively encode the highly conserved amino-terminal domain (the beta-granin sequence). Exon VI encodes a variable domain within which is the chromostatin sequence, and exon VII encodes another variable domain, which contains the pancreastatin sequence. Exon VIII encodes the highly conserved carboxyl-terminal domain and the 3'-noncoding region. The human gene promoter has a consensus TATA box, cAMP response element, and Sp-I sequence. 2.3 kilobases of the upstream regulatory region of the human CgA gene directed efficient transcription of a reporter chloramphenicol acetyltransferase gene in several neuroendocrine cell lines, including human medullary thyroid C-cell tumor, mouse pituitary corticotroph, rat pituitary tumor, and rat pheochromocytoma. The promoter was virtually inactive in nonneuroendocrine cell lines. Transient transfection studies with deleted promoter constructs showed that sequences lying between -55 and +32 base pairs relative to the transcription initiation site, containing the consensus cyclic AMP response element and TATA box, were sufficient for neuroendocrine cell-specific expression.
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PMID:Human chromogranin A gene. Molecular cloning, structural analysis, and neuroendocrine cell-specific expression. 812 54

In Trypanosoma brucei, pre-mRNAs are joined to a 5' 39 nt spliced leader sequence by trans splicing, a process that has not been well characterized. We have asked whether the 3' splice site regions of human and yeast introns are able to substitute in vivo for the 3' spliced leader acceptor regions of trypanosome pre-mRNA sequences. The ability of heterologous sequences to participate in trans splicing in trypanosomes was assayed by chloramphenicol acetyltransferase (CAT) enzyme activity and/or the detection of spliced CAT mRNA. Four out of the six heterologous 3' splice site regions (human beta-globin intervening sequence (IVS)2, human c-myc IVS2, human factor-VIII IVS1, and yeast actin IVS) functioned as 3' spliced leader acceptor regions in T. brucei, while two did not show significant or detectable levels of CAT activity (human beta-globin IVS1 and human c-myc IVS1). In the case of the human beta-globin IVS1 however, lengthening of the polypyrimidine tract as a result of single purine to pyrimidine transversions produced an active acceptor in which the spliced leader addition site coincides with the 3' splice site of the beta-globin exon 2. These studies indicate that some, but not all 3' acceptor regions in humans can function as spliced leader addition sites in trypansomes.
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PMID:Human and fungal 3' splice sites are used by Trypanosoma brucei for trans splicing. 901 Aug 38