ISSN:
1432-1432
Keywords:
Collagen
;
Ancestral genetic domain
;
Simple sequence amplification
;
Consensus sequence
;
Introns
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary Although the major types of vertebrate collagen have a number of structural properties in common, significant DNA sequence homologies have not been detected between different portions of the helical coding domains within the same gene or between different genes. However, under non-stringent hybridization conditions we found considerable cross-homology within and between α1(I) and α2(I) chick cDNAs in the coding regions for helical sequences. Detailed analyses at the DNA sequence level have led us to propose that the gene for chick pro α2(I) collagen arose from a 9-bp primordial sequence. A consensus sequence for the 9-bp repeat was derived: GGTCCTCCT, which codes for a Gly-Pro-Pro triplet. The primordial ancestor of this 9-bp unit, GGTCCTXCT, apparently underwent duplication and divergence. Each resulting 9-bp sequence was triplicated to form a 27-bp domain, and a condensation event produced a 54-bp domain. This genetic unit then underwent multiple rounds of amplification to form the ancestral gene for the full-length helical section of α2(I). A different 9-bp consensus sequence (GGTCCCCCC) seems to have been the basis of the chick pro α1(I) gene.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02099750
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