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Molecular cloning, sequence, and tissue distribution of the human ubiquitin-activating enzyme E1.

ABSTRACT: The ubiquitin-activating enzyme E1 catalyzes the first step in ubiquitin conjugation. We have cloned and sequenced the cDNA for human E1. This clone predicts a protein of 110,450 Da. Cys-194 lies within a region of identity to active-site Cys-88 of the ubiquitin carrier protein E2, suggesting a potential role for this region in enzymatic function of this protein. In addition, Cys-454 lies within a region of identity to the thiol ester consensus sequence of several proteins involved in thioester formation. Tissue distribution reveals a single 3.5-kilobase E1 message ubiquitous among tissues and cell lines.

SUBMITTER: Handley PM

PROVIDER: S-EPMC50789 | biostudies-other | 1991 Jan

REPOSITORIES: biostudies-other

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Molecular cloning, sequence, and tissue distribution of the human ubiquitin-activating enzyme E1.

Handley P M PM Mueckler M M Siegel N R NR Ciechanover A A Schwartz A L AL

Proceedings of the National Academy of Sciences of the United States of America 19910101 1

The ubiquitin-activating enzyme E1 catalyzes the first step in ubiquitin conjugation. We have cloned and sequenced the cDNA for human E1. This clone predicts a protein of 110,450 Da. Cys-194 lies within a region of identity to active-site Cys-88 of the ubiquitin carrier protein E2, suggesting a potential role for this region in enzymatic function of this protein. In addition, Cys-454 lies within a region of identity to the thiol ester consensus sequence of several proteins involved in thioester ...[more]

PMID: 1986373

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