Organisation and sequence studies of the 17-piece chicken conalbumin gene

Abstract

The conalbumin gene has been cloned and shown to consist of at least 17 exons approximately 60-200 base pairs long. The DNA sequence upstream from the region coding for the 5' end of the mRNA shows similarities with sequences present in homologous positions in other genes. High and low frequency repetitive sequences are found both upstream from the conalbumin gene and within one intron.

The Complete Nucleotide Sequence of the Chicken Ovotransferrin mRNA

“…All of the restriction sites used for sequencing were overlapped with the exception of the two TuqI sites [I] located at the extremities of the conalbumin dscDNA insert. {We are, however, confident that no Taql fragment was overlooked, since one of the TuqI sites is located at the 3' end of the mRNA poly(A) tail, while the other is situated at the 5' end of the cloned dscDNA in a region which was previously sequenced in the cloned chromosomal ovotransferrin gene [2].} Most of the sequencing operations were performed on the two DNA strands with the exception of about 300 base pairs i n a region located at the 3' end of the dscDNA, where sequencing was repeated twice from the BglII and TuqI sites.…”

“…This sequence, together with the previously reported sequence of the 5' end of the ovotransferrin gene [2], provides a complete sequence of chicken ovotransferrin mRNA and protein.…”

“…Determination of partial amino-acid sequences of the N-terminal and C-terminal ends of the protein, X-ray crystallography studies and partial proteolysis experiments on human, chicken and rabbit transferrins have led to the hypothesis that the present-day transferrin gene has evolved by duplication from an ancestral gene [7-101. Moreover, it has been proposed that this ancestral gene could be itself the product of a more ancient duplication [8] and, therefore, that the present-day transferrins could be the product of a quadruplication event.We have previously reported that the chicken transferrin gene is split in 17 exons [2]. The complete elucidation of the structure of the transferrin gene a t the sequence level should reveal some of the mechanisms involved in the generation of split genes by duplication and possibly quadruplication of ancestral genes.…”

“…We have previously reported that the chicken transferrin gene is split in 17 exons [2]. The complete elucidation of the structure of the transferrin gene a t the sequence level should reveal some of the mechanisms involved in the generation of split genes by duplication and possibly quadruplication of ancestral genes.…”

“…The liver and the oviduct proteins differ only in the nature of their attached glycan chain [3,41. However, the modulation of the expression of the transferrin gene by steroid hormones and iron levels is very different in the two organs [2,5,61. Determination of partial amino-acid sequences of the N-terminal and C-terminal ends of the protein, X-ray crystallography studies and partial proteolysis experiments on human, chicken and rabbit transferrins have led to the hypothesis that the present-day transferrin gene has evolved by duplication from an ancestral gene [7-101. Moreover, it has been proposed that this ancestral gene could be itself the product of a more ancient duplication [8] and, therefore, that the present-day transferrins could be the product of a quadruplication event.…”