Molecular characterization of a fourth isoform of the catalytic subunit of protein phosphatase 2A from Arabidopsis thaliana
Tóm tắt
We have recently reported the existence of multiple isoforms of the catalytic subunit of protein phosphatase 2A (PP2A) in Arabidopsis thaliana and the molecular cloning of cDNAs encoding three of these proteins (PP2A-1, PP2A-2, PP2A-3). The reported cDNA encoding PP2A-3 was truncated at the 5′ terminus, lacking a short fragment of the N-terminal coding sequence. We have now isolated a near full-length cDNA encoding the entire PP2A-3 protein (313 residues). The clone includes 188 nucleotides of 5′-untranslated region, where a 44 bp long poly(GA) track is found. We also describe the cloning of a cDNA encoding a fourth isoform of PP2A (PP2A-4). The polypeptide contains 313 residues being 98% identical to PP2A-3 and only 80% identical to both PP2A-1 and PP2A-2. The mRNA for PP2A-4 is 1.4 kb in length and, although predominantly expressed in roots, it is also found in other organs. It is concluded that in A. thaliana the isoforms of PP2A can be grouped in two extremely conserved subfamilies.
Tài liệu tham khảo
Ariño J, Woon CW, Brautigan DL, Miller TB, Johnson GL: Human liver phosphatase 2A: cDNA and amino acid sequence of two catalytic subunits isotypes. Proc Natl Acad Sci USA 85: 4252–4256 (1988).
Ariño J, Pérez-Callejón E, Cunillera N, Camps M, Posas F, Ferrer A: Protein phosphatases in higher plants: multiplicity of type 2A ‘phosphatases in Arabidopsis thaliana. Plant Mol Biol 21: 475–485 (1993).
Berunés J, Beltrán R, Azorín F: SV40 recombinants carrying a d(CT.GA)22 sequence show increased genomic instability. Gene 108: 269–274 (1991).
Cormier P, Osborne HB, Bassez T, Poulhe R, Bellé R, Mulner-Lorillon O: Protein phosphatase 2A from Xenopus oocytes: characterization during meiotic cell division. FEBS Lett 295: 185–188 (1991).
Dean L, Elzen B, Tamaki S, Dunsmuir P, Bedbrook J: Differential expression of the eight genes of the petunia ribulose bisphosphate carboxylase small subunit multigene family. EMBO J 5: 3055–3061 (1985).
Dellaporta SL, Wood J, Hicks JB: Maize DNA miniprep. In. Molecular Biology of Plants: A Laboratory Manual, pp. 36–37. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY (1984).
Dombràdi V, Mann DJ, Saunders RDC, Cohen PTW: Cloning of the fourth functional gene for protein phosphatase 1 in Drosophila melanogaster from its chromosomal location. Eur J Biochem 212: 177–183 (1993).
Erondu NE, Donelson JE: Characterization of trypanosome protein phosphatase 1 and 2A catalytic subunits. Mol Biochem Parasitol 49: 303–314 (1991).
Gerlach WL, Bedbrook JR: Cloning and characterization of ribosomal RNA genes from wheat and barley. Nucl Acids Res 7: 1869–1885 (1979).
Hubbard MJ, Cohen P: On target with a new mechanism for the regulation of protein phosphorylation. Trends Biochem Sci 18: 172–177 (1993).
Hunt H, Lund E, Dalberg JE: Human U1 RNA genes contain an unusually sensitive nuclease S1 cleavage site within the conserved 3′-flanking region. Proc Natl Acad Sci USA 81: 7288–7292 (1984).
Kinoshita N, Ohkura H, Yanagida M: Distinct, essential roles of type 1 and 2A protein phosphatases in the control of the fission yeast cell division cycle. Cell 63: 405–415 (1990).
Lütcke HA, Chow KC, Mickel FS, Moss KA, Kern HF, Scheele GA: Selection of AUG initiation codons differs in plants and animals. EMBO J 6: 43–48 (1987).
Manor H, Sridhara Rao B, Martin RG: Abundance and degree of dispersion of genomic d(GA)n.d(CT)n sequences. J Mol Evol 27: 96–101 (1988).
Nitschke K, Fleig U, Schell J, Palme K: Complementation of the cs dis2–11 cell cycle mutant of Schizosaccharomyces pombe by a protein phosphatase 1. EMBO J 11: 1327–1333 (1992).
Orgad S, Brewis ND, Alphey L, Axton JM, Dudai Y, Cohen PTW: The structure of protein phosphatase 2A is as highly conserved as that of protein phosphatase 1. FEBS Lett 275: 44–48 (1990).
Palecek E: Local supercoil-stabilized DNA structures. CRC Crit Rev Biochem Mol Biol 26: 151–226 (1991).
Pérez-Callejón E, Casamayor A, Pujol G, Clua E, Ferrer A, Ariño J: Identification and molecular cloning of two homologues of protein phosphatase X from Arabidopsis thaliana. Plant Mol Biol 23: 1177–1185 (1993).
Pirk M, Páy A, Heberle-Bors E, Hirt H: Isolation and characterization of a phosphoprotein phosphatase type 2A gene from alfalfa. Mol Gen Genet 240: 126–131 (1993).
Ronne H, Carlberg M, Hu G-Z, Nehlin JO: Protein phosphatase 2A in Saccharomyces cerevisiae: effects on cell growth and bud morphogenesis. Mol Cell Biol 11: 4876–4883 (1991).
Sanger F, Nicklen S, Coulson AR: DNA sequencing with chain terminating inhibitors. Proc Natl Acad Sci USA 74: 5463–5467 (1977).
Sasaki K, Shima H, Kitagawa Y, Irino S, Sugimura T, Nagao M: Identification of members of the protein phosphatase 1 gene family in the rat and enhanced expression of the protein phosphatase 1α gene in rat hepatocellular carcinomas. Jpn J Cancer Res 81: 1272–1280 (1990).
Sheen J: Protein phosphatase activity is required for lightinducible gene expression in maize. EMBO J 12: 3497–3505 (1993).
Smith RD, Walker JC: Expression of multiple type 1 phosphoprotein phosphatases in Arabidopsis thaliana. Plant Mol Biol 21: 307–316 (1993).
Sneddon AA, Cohen PTW, Stark MJR: Saccharomyces cerevisiae protein phosphatase 2A performs an essential cellular function and is encoded by two genes. EMBO J 9: 4339–4346 (1990).
Wadzinsky BE, Heasley LE, Johnson GL: Multiplicity of protein serine-threonine phosphatases in PC12 pheocromocytoma and FTO-2B hepatoma cells. J Biol Chem 265: 21504–21508 (1990).