Isolation and sequence of a cDNA encoding mouse IMP dehydrogenase.

A A Tiedeman; J M Smith

doi:10.1016/0378-1119(91)90065-j

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Isolation and sequence of a cDNA encoding mouse IMP dehydrogenase.

A A Tiedeman·J M Smith

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Abstract

Inosinic acid (IMP) dehydrogenase (IMPD) catalyzes the conversion of IMP to XMP as the first committed step in GMP biosynthesis de novo. We have isolated a cDNA containing the complete coding region of mouse IMPD by its ability to complement a bacterial mutant lacking IMPD activity. Two independent cDNA clones were isolated by complementation, of which the longest was 1.7 kb in length. Northern analyses, using the IMPD cDNA as a probe, indicated that mature IMPD mRNA was a single species approx. 2.0 kb in size. Mouse IMPD is almost identical to Chinese hamster and human IMPDs and is highly conserved between Escherichia coli and mouse, with a direct amino acid (aa) identity of 39%, which increases to 60% if conserved aa are considered. The leader region of our longest cDNA clone is G + C-rich and contains two tandem copies of a G + C-rich direct repeat.

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Amino Acid Sequence Animals Base Sequence Blotting, Northern Cloning, Molecular Cricetinae DNA Escherichia coli Genetic Complementation Test Humans IMP Dehydrogenase Mice Molecular Sequence Data Restriction Mapping Sequence Alignment Sequence Homology, Nucleic Acid Journal Article Research Support, U.S. Gov't, P.H.S.

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A A Tiedeman, J M Smith. 1991-01-15. Isolation and sequence of a cDNA encoding mouse IMP dehydrogenase.. https://doi.org/10.1016/0378-1119(91)90065-j

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