Biomaterial Database

The catalytic subunit of protein phosphatase 2A is carboxyl-methylated in vivo. 1994

B Favre, and S Zolnierowicz, and P Turowski, and B A Hemmings

Friedrich Miescher-Institut, Basel, Switzerland.

We have used polyclonal antibodies against an internal peptide (residues 169 to 182; Ab169/182) and a peptide corresponding to the carboxyl terminus (residues 299 to 309; Ab299/309) to look for in vivo modifications of protein phosphatase 2A catalytic (PP2Ac) subunit. Treatment of extracts from human breast cancer (MCF7) cells with either alkali or ethanol increased immunoreactivity of PP2Ac subunit severalfold on Western blots with Ab299/309, but did not apparently change molecular weight or isoelectric point of the protein. In contrast, immunoreactivity with Ab169/182 was unchanged by these treatments. Subsequently, we demonstrated that the increase in PP2Ac subunit recognition by Ab299/309 coincides with the demethylation of this protein at the carboxyl-terminal leucine (Leu309). Methylation of PP2Ac subunit, in vitro, increases its activity toward both phosphorylase a and a phosphopeptide. The carboxyl-terminal sequence (TPDYFL) of PP2Ac subunit is completely conserved between mammals, yeast, fruit fly, and plants which suggests that regulation of this enzyme activity by carboxyl-terminal methylation has been conserved during evolution.

UI	MeSH Term	Description	Entries
D007930	Leucine	An essential branched-chain amino acid important for hemoglobin formation.	L-Leucine,Leucine, L-Isomer,L-Isomer Leucine,Leucine, L Isomer
D008745	Methylation	Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed)	Methylations
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D009842	Oligopeptides	Peptides composed of between two and twelve amino acids.	Oligopeptide
D010749	Phosphoprotein Phosphatases	A group of enzymes removing the SERINE- or THREONINE-bound phosphate groups from a wide range of phosphoproteins, including a number of enzymes which have been phosphorylated under the action of a kinase. (Enzyme Nomenclature, 1992)	Phosphoprotein Phosphatase,Phosphoprotein Phosphohydrolase,Protein Phosphatase,Protein Phosphatases,Casein Phosphatase,Ecto-Phosphoprotein Phosphatase,Nuclear Protein Phosphatase,Phosphohistone Phosphatase,Phosphoprotein Phosphatase-2C,Phosphoseryl-Protein Phosphatase,Protein Phosphatase C,Protein Phosphatase C-I,Protein Phosphatase C-II,Protein Phosphatase H-II,Protein-Serine-Threonine Phosphatase,Protein-Threonine Phosphatase,Serine-Threonine Phosphatase,Threonine Phosphatase,Ecto Phosphoprotein Phosphatase,Phosphatase C, Protein,Phosphatase C-I, Protein,Phosphatase C-II, Protein,Phosphatase H-II, Protein,Phosphatase, Casein,Phosphatase, Ecto-Phosphoprotein,Phosphatase, Nuclear Protein,Phosphatase, Phosphohistone,Phosphatase, Phosphoprotein,Phosphatase, Phosphoseryl-Protein,Phosphatase, Protein,Phosphatase, Protein-Serine-Threonine,Phosphatase, Protein-Threonine,Phosphatase, Serine-Threonine,Phosphatase, Threonine,Phosphatase-2C, Phosphoprotein,Phosphatases, Phosphoprotein,Phosphatases, Protein,Phosphohydrolase, Phosphoprotein,Phosphoprotein Phosphatase 2C,Phosphoseryl Protein Phosphatase,Protein Phosphatase C I,Protein Phosphatase C II,Protein Phosphatase H II,Protein Phosphatase, Nuclear,Protein Serine Threonine Phosphatase,Protein Threonine Phosphatase,Serine Threonine Phosphatase
D010762	Phosphorylase a	The active form of GLYCOGEN PHOSPHORYLASE that is derived from the phosphorylation of PHOSPHORYLASE B. Phosphorylase a is deactivated via hydrolysis of phosphoserine by PHOSPHORYLASE PHOSPHATASE to form PHOSPHORYLASE B.
D010766	Phosphorylation	The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.	Phosphorylations
D011496	Protein Methyltransferases	Enzymes that catalyze the methylation of amino acids after their incorporation into a polypeptide chain. S-Adenosyl-L-methionine acts as the methylating agent. EC 2.1.1.	Protein Methylase,Protein Methylases,Protein Methyltransferase,Methylase, Protein,Methylases, Protein,Methyltransferase, Protein,Methyltransferases, Protein
D011499	Protein Processing, Post-Translational	Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.	Amino Acid Modification, Post-Translational,Post-Translational Modification,Post-Translational Protein Modification,Posttranslational Modification,Protein Modification, Post-Translational,Amino Acid Modification, Posttranslational,Post-Translational Amino Acid Modification,Post-Translational Modifications,Post-Translational Protein Processing,Posttranslational Amino Acid Modification,Posttranslational Modifications,Posttranslational Protein Processing,Protein Processing, Post Translational,Protein Processing, Posttranslational,Amino Acid Modification, Post Translational,Modification, Post-Translational,Modification, Post-Translational Protein,Modification, Posttranslational,Modifications, Post-Translational,Modifications, Post-Translational Protein,Modifications, Posttranslational,Post Translational Amino Acid Modification,Post Translational Modification,Post Translational Modifications,Post Translational Protein Modification,Post Translational Protein Processing,Post-Translational Protein Modifications,Processing, Post-Translational Protein,Processing, Posttranslational Protein,Protein Modification, Post Translational,Protein Modifications, Post-Translational
D001943	Breast Neoplasms	Tumors or cancer of the human BREAST.	Breast Cancer,Breast Tumors,Cancer of Breast,Breast Carcinoma,Cancer of the Breast,Human Mammary Carcinoma,Malignant Neoplasm of Breast,Malignant Tumor of Breast,Mammary Cancer,Mammary Carcinoma, Human,Mammary Neoplasm, Human,Mammary Neoplasms, Human,Neoplasms, Breast,Tumors, Breast,Breast Carcinomas,Breast Malignant Neoplasm,Breast Malignant Neoplasms,Breast Malignant Tumor,Breast Malignant Tumors,Breast Neoplasm,Breast Tumor,Cancer, Breast,Cancer, Mammary,Cancers, Mammary,Carcinoma, Breast,Carcinoma, Human Mammary,Carcinomas, Breast,Carcinomas, Human Mammary,Human Mammary Carcinomas,Human Mammary Neoplasm,Human Mammary Neoplasms,Mammary Cancers,Mammary Carcinomas, Human,Neoplasm, Breast,Neoplasm, Human Mammary,Neoplasms, Human Mammary,Tumor, Breast