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Molecular cloning and chromosome mapping of the human gene encoding protein phosphotyrosyl phosphatase 1B.

ABSTRACT: The inactivation of growth suppressor genes appears to play a major role in the malignant process. To assess whether protein phosphotyrosyl phosphatases (protein-tyrosine-phosphate phosphohydrolase, EC 3.1.3.48) function as growth suppressors, we have isolated a cDNA clone encoding human protein phosphotyrosyl phosphatase 1B for structural and functional characterization. The translation product deduced from the 1305-nucleotide open reading frame predicts a protein containing 435 amino acids and having a molecular mass of 49,966 Da. The amino-terminal 321 amino acids deduced from the cDNA sequence are identical to the empirically determined sequence of protein phosphotyrosyl phosphatase 1B. [Charbonneau, H., Tonks, N. K., Kumar, S., Diltz, C. D., Harrylock, M., Cool, D. E., Krebs, E. G., Fischer, E. H. & Walsh, K. A. (1989) Proc. Natl. Acad. Sci. USA 86, 5252-5256]. A genomic clone has been isolated and used in an in situ hybridization to banded metaphase chromosomes to determine that the gene encoding protein phosphotyrosyl phosphatase 1B maps as a single-copy gene to the long arm of chromosome 20 in the region q13.1-q13.2.

SUBMITTER: Brown-Shimer S

PROVIDER: S-EPMC54279 | biostudies-other | 1990 Jul

REPOSITORIES: biostudies-other

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Molecular cloning and chromosome mapping of the human gene encoding protein phosphotyrosyl phosphatase 1B.

Brown-Shimer S S Johnson K A KA Lawrence J B JB Johnson C C Bruskin A A Green N R NR Hill D E DE

Proceedings of the National Academy of Sciences of the United States of America 19900701 13

The inactivation of growth suppressor genes appears to play a major role in the malignant process. To assess whether protein phosphotyrosyl phosphatases (protein-tyrosine-phosphate phosphohydrolase, EC 3.1.3.48) function as growth suppressors, we have isolated a cDNA clone encoding human protein phosphotyrosyl phosphatase 1B for structural and functional characterization. The translation product deduced from the 1305-nucleotide open reading frame predicts a protein containing 435 amino acids and ...[more]

PMID: 2164224

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Project description:BackgroundFlavonol glycosides (FGs) are major components of soybean leaves and there are substantial differences in FG composition among genotypes. The first objective of this study was to identify genes responsible for FG biosynthesis and to locate them in the soybean genome. The second objective was to clone the candidate genes and to verify their function. Recombinant inbred lines (RILs) were developed from a cross between cultivars Nezumisaya and Harosoy.ResultsHPLC comparison with authentic samples suggested that FGs having glucose at the 2″-position of glucose or galactose that is bound to the 3-position of kaempferol were present in Nezumisaya, whereas FGs of Harosoy were devoid of 2″-glucose. Conversely, FGs having glucose at the 6″-position of glucose or galactose that is bound to the 3-position of kaempferol were present in Harosoy, whereas these FGs were absent in Nezumisaya. Genetic analysis suggested that two genes control the pattern of attachment of these sugar moieties in FGs. One of the genes may be responsible for attachment of glucose to the 2″-position, probably encoding for a flavonol 3-O-glucoside/galactoside (1 → 2) glucosyltransferase. Nezumisaya may have a dominant whereas Harosoy may have a recessive allele of the gene. Based on SSR analysis, linkage mapping and genome database survey, we cloned a candidate gene designated as GmF3G2″Gt in the molecular linkage group C2 (chromosome 6). The open reading frame of GmF3G2″Gt is 1380 bp long encoding 459 amino acids with four amino acid substitutions among the cultivars. The GmF3G2″Gt recombinant protein converted kaempferol 3-O-glucoside to kaempferol 3-O-sophoroside. GmF3G2″Gt of Nezumisaya showed a broad activity for kaempferol/quercetin 3-O-glucoside/galactoside derivatives but it did not glucosylate kaempferol 3-O-rhamnosyl-(1 → 4)-[rhamnosyl-(1 → 6)-glucoside] and 3-O-rhamnosyl-(1 → 4)-[glucosyl-(1 → 6)-glucoside].ConclusionGmF3G2″Gt encodes a flavonol 3-O-glucoside/galactoside (1 → 2) glucosyltransferase and corresponds to the Fg3 gene. GmF3G2″Gt was designated as UGT79B30 by the UGT Nomenclature Committee. Based on substrate specificity of GmF3G2″Gt, 2″-glucosylation of flavonol 3-O-glycoside may be irreconcilable with 4″-glycosylation in soybean leaves.

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Dataset Information

Molecular cloning and chromosome mapping of the human gene encoding protein phosphotyrosyl phosphatase 1B.

Publications

Molecular cloning and chromosome mapping of the human gene encoding protein phosphotyrosyl phosphatase 1B.

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