ISSN:
1432-1203
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract cDNA clones for the human Leydig insulin-like peptide (Ley I-L) have been isolated and characterized. The nucleotide sequence of the 743-bp cDNA includes an incomplete 7-bp 5′-noncoding region, an open reading frame of 393 bp, and a 343-bp 3′-noncoding region. By primer extension analysis, the transcription start site was determined as being 14-bp upstream of the translation start site. The underlying gene is expressed in the testis but not in other organs. From the cDNA sequence, it can be deduced that the Ley I-L protein is synthesized as a 131-amino-acid (aa) preproprotein and that it contains a 24-aa signal peptide. Comparison of the pro Ley I-L protein with members of the insulin-like hormone superfamily predicts that the biologically active hormone, after proteolytic processing of the C peptide, consists of a 31-aa long B chain and a 26-aa long A chain, and that it has a molecular weight of 6.25 kDa.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02272850
