ISSN:
1617-4623
Keywords:
Key words S‐adenosyl‐l‐homocysteine hydrolase
;
Amino acid sequence
;
Cytological mapping
;
Drosophila melanogaster
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract S-adenosyl-l-homocysteine hydrolase (AdoHcyase, EC 3.3.1.1) catalyzes the hydrolysis of S-adenosyl-l-homocysteine to adenosine and homocysteine and thus plays a crucial role in normal cellular metabolism. We have isolated the cDNA for Drosophila melanogaster AdoHcyase by screening a Drosophila ovarian expression library. The 1584-nucleotide cDNA encodes a protein of 431 amino acids, showing 80.5% identity with human AdoHcyase. Southern analysis of genomic DNA and in situ hybridization to salivary gland chromosomes indicate that a single gene encodes the D. melanogaster AdoHcyase. The gene resides in region 13C1-2 on the X chromosome. Transcript analysis shows a single AdoHcyase mRNA present in unfertilized eggs, and, at a more or less constant level of expression, in all developmental stages tested, ranging from early embryos to adults. The deduced amino acid sequence was compared to a putative AdoHcyase-like protein encoded by a cDNA mapping to the 89E region of the second chromosome and showing much lower similarity to known AdoHcyases. We discuss the hypothesis that a sequence that originated by duplication of an ancestral AdoHcyase gene has, in the course of evolution, been recruited to supply a different function.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004380050348
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