Two different sequence elements within exon 4 are necessary for calcitonin-specific splicing of the human calcitonin/calcitonin gene-related peptide I pre-mRNA.
AUTOR(ES)
van Oers, C C
RESUMO
The calcitonin (CT)/calcitonin gene-related peptide I (CGRP-I) gene (CALC-I gene) is subject to alternative tissue-specific processing of its primary transcript. CT mRNA is the predominant mRNA produced in thyroid C cells, whereas CT gene-related peptide I mRNA is the main product in neurons of the central and peripheral nervous systems. The CT-specific exon 4 is surrounded by weak processing sites. In this study we have investigated whether exon 4 sequences are involved in the tissue-specific selection of the exon 4 splice acceptor site. The results indicate that two separate elements, termed A and B, in the 5' part of exon 4 are required for production of CT-specific RNA. These sequences are located between nucleotides 67 and 88 (A) and nucleotides 117 and 146 (B) relative to the 5' end of exon 4. Variation of the distance between these sequence elements and the 3' splice site of exon 4 does not change the processing choice. These sequence elements are functionally equivalent. CT-specific splicing requires the presence of both sequence A and B or duplicates of either sequence element in exon 4. The effect of these sequences on the RNA processing choice is overruled by mutation of the CT-specific uridine branch acceptor nucleotide into a commonly preferred adenosine residue.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=358450Documentos Relacionados
- Control of calcitonin/calcitonin gene-related peptide pre-mRNA processing by constitutive intron and exon elements.
- Alternative RNA processing events in human calcitonin/calcitonin gene-related peptide gene expression.
- Calcitonin/calcitonin gene-related peptide transcription unit: tissue-specific expression involves selective use of alternative polyadenylation sites.
- An intron enhancer containing a 5' splice site sequence in the human calcitonin/calcitonin gene-related peptide gene.
- Retinoic acid repression of cell-specific helix-loop-helix-octamer activation of the calcitonin/calcitonin gene-related peptide enhancer.