Regulation of expression of the alpha 1 (I) collagen gene: a critical appraisal of the role of the first intron.
The transcriptional regulation of the genes encoding the alpha 1 (I) collagen chains is necessarily complex since these genes are expressed at widely different levels, and in a cell- and tissue-specific fashion. In the case of the alpha 1 (I) gene, there is substantial, but controversial, evidence for an involvement of the first intron in the tissue-specific expression of the gene. This evidence is based largely on transfection of cells with collagen-reporter gene constructs and on studies of transgenic mice. In this review, I propose a number of reason for the conflicting data in the literature: 1) the cell-specific nature of the intronic effect; thus, not all cultured, collagen-synthesizing cells will demonstrate an intronic effect by transfection; 2) the possibility that functionally equivalent regulatory elements are placed in different regions of the alpha 1 (I) gene in different species; and 3) the possibility that functionally redundant sequences exist within the alpha 1 (I) gene, which would permit other regions to substitute for the first intron.
Bornstein
P
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Department of Biochemistry University of Washington, Seattle, Washington, USA.
D000818:Animals; D002148:Calmodulin-Binding Proteins / Q000235:genetics; D003094:Collagen / Q000096:biosynthesis / Q000235:genetics*; D005786:Gene Expression Regulation; D013006:Growth Hormone / Q000235:genetics; D006801:Humans; D007438:Introns; D051379:Mice; D008822:Mice, Transgenic; D009928:Organ Specificity; D014158:Transcription, Genetic; D014162:Transfection / Q000379:methods
D002148:Calmodulin-Binding Proteins; C051666:calspermin; D013006:Growth Hormone; D003094:Collagen