The complete sequence of the chicken α-cardiac actin gene: a highly conserved vertebrate gene

Abstract

We sequenced the entire chicken α-cardiac actin gene. A single intron was positioned 20 bp upstream from the initiation ATG codon in the 5′ non-coding region while the coding region was interrupted by 5 introns at amino acid positions 41/42, 150, 204, 267, and 327/328.Sequencing allowed the first comparison of the α-cardiac and α-skeletal actin transcriptional promoters. These highly G+C rich promoters share two regions of homology which are found at position −134 (10 bp) end −296 (12 bp) in the α-cardiac actin promoter. A smaller 9 bp motif (CCGCCCCGG) homologous to the −134 sequence was detected before, between and after the TATA and CAAT boxes of the α-cardiac actin gene. The polyadenylation signal (AATAAA) was located 156 bp downstream from the translation termination codon. The complete length of the α-cardiac actin mRNA excluding the poly A tail is 1370 nucleotides. The 3′ noncoding transcribed portion of the chicken α-cardiac actin gene was found to be extraordinarily conserved when compared to the human and rat α-cardiac actin mRNA sequences.