Molecular cloning and nucleotide sequence for the complete coding region of human UMP synthase

Journal Article · Tue Mar 01 04:00:00 EST 1988 · Proceedings of the National Academy of Sciences of the United States of America; (USA)

DOI:https://doi.org/10.1073/pnas.85.6.1754· OSTI ID:6829206

Suttle, D P ^[1]; Bugg, B Y ^[2]; Winkler, J K ^[3]; Kanalas, J J ^[4]

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1. St. Jude Children's Research Hospital, Memphis, TN (USA) Veterans Administration Medical Center, Memphis, TN (USA)
2. Veterans Administration Medical Center, Memphis, TN (USA)
3. St. Jude Children's Research Hospital, Memphis, TN (USA)
4. Univ. of Texas Health Science Center, San Antonio (USA)

The last two steps in the de novo biosynthesis of UMP are catalyzed by orotate phosphoribosyltransferase and orotidine-5{prime}-monophosphate decarboxylase. In mammals these two activities are found in a single, bifunctional protein called UMP synthase. A human T-lymphoblastic cell cDNA library constructed in {lambda}gt10 was screened with a UMP synthase-specific rat cDNA probe. Human UMP synthase cDNAs were isolated and then used to select UMP synthase gene fragments. The complete coding sequence of the mRNA for UMP synthase was determined by analysis of overlapping cDNA and genomic fragments. One of the cDNAs appears to have been synthesized from an incompletely or alternatively processed form of the UMP synthase mRNA. This cDNA lacks a poly(A) tail and has an extended 3{prime}-nontranslated region that hybridizes with larger forms of the UMP synthase mRNA. The UMP synthase protein is composed of 480 amino acids with a molecular weight of 52,199. The two activities of UMP synthase reside in distinct domains encoded by the 3{prime} and 5{prime} halves of the mRNA. The COOH-terminal 258 amino acids of the human UMP synthase protein contain the orotidine-5{prime}-monophosphate decarboxylase catalytic domain. This region is highly homologous to the mouse orotidine-5{prime}-monophosphate decarboxylase sequence. The NH{sub 2}-terminal 214 amino acids contain the OPRT domain. There is amino acid homology between this protein domain and specific regions of the Escherichia coli OPRT. The human OPRT domain also contains the putative catalytic site common to other human phosphoribosyltransferases.

• OSTI ID: 6829206
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (USA), Journal Name: Proceedings of the National Academy of Sciences of the United States of America; (USA) Vol. 85:6; ISSN PNASA; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACID SEQUENCE
ANIMALS
AZINES
BIOLOGICAL EVOLUTION
CARBON-CARBON LYASES
CARBOXY-LYASES
CARBOXYLIC ACIDS
CLONING
DNA
DNA HYBRIDIZATION
DNA SEQUENCING
DNA-CLONING
ENZYMES
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYBRIDIZATION
HYDROXY COMPOUNDS
LYASES
MAMMALS
MESSENGER-RNA
MICE
MOLECULAR STRUCTURE
NUCLEIC ACIDS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OROTIC ACID
PHOSPHORUS-GROUP TRANSFERASES
PHOSPHOTRANSFERASES
PYRIMIDINES
RECOMBINANT DNA
RIBOSIDES
RNA
RODENTS
STRUCTURAL CHEMICAL ANALYSIS
TRANSFERASES
URACILS
VERTEBRATES