Avian keratin genes. I. A molecular analysis of the structure and expression of a group of feather keratin genes.
The nucleotide sequence of the four complete chicken feather keratin genes A to D contained in the previously isolated recombinant lambda CFK1 has been determined. All four genes have a very similar structure; each gene encodes a polypeptide of 97 amino acid residues and contains an intron in the 5' non-coding region, 37 base-pairs from the cap site. Comparison of the previously determined feather keratin gene C sequence to genes A, B and D indicates that a high level of gene correction has occurred in the protein coding and 5' non-coding regions, which show more than 90% homology, whereas the intron and 3' non-coding regions are by contrast poorly conserved with one or two exceptions. The dramatic conservation of the 5' non-coding region between the feather keratin sequences and an unrelated but co-expressed gene encoding a histidine-rich protein suggests that this segment may play an important role in transcriptional regulation. In addition, both gene types contain an identically positioned intron in the 5' non-coding region. Northern blots performed using gene-specific probes show that the four characterized genes A to D plus gene E, which is partially contained in the recombinant lambda CFK1, are all expressed in feather tissue from 14-day old chick embryos. In addition, we report that a scale keratin gene (originally isolated from a scale complementary DNA library) is expressed at a low level in the embryonic feather.
Presland
R B
RB
Department of Biochemistry, University of Adelaide, South Australia.
Gregg
K
K
Molloy
P L
PL
Morris
C P
CP
Crocker
L A
LA
Rogers
G E
GE
D000818:Animals; D001482:Base Composition; D001483:Base Sequence; D002642:Chick Embryo; D005241:Feathers / Q000032:analysis*; D015870:Gene Expression; D005796:Genes; D007438:Introns; D007633:Keratins / Q000235:genetics*; D008969:Molecular Sequence Data; D015183:Restriction Mapping; D014158:Transcription, Genetic
D007633:Keratins