Identification of cytosolic Mg2+-dependent soluble inorganic pyrophosphatases in potato and phylogenetic analysis.
Using polyclonal antibodies raised against a previously cloned potato Mg2+-dependent soluble inorganic pyrophosphatase (ppa1 gene) [8], a second gene, called ppa2, could be isolated. A single locus homologous to ppa2 was mapped on potato chromosomes, unlinked to the two loci identified for ppa1. From a phylogenetic and structural point of view, the PPA1 and PPA2 polypeptides are more closely related to prokaryotic than to eukaryotic Mg2+-dependent soluble inorganic pyrophosphatases (soluble PPases). Subcellular localization by immunogold electron microscopy, using sections from leaf parenchyma cells, showed that PPA and PPA2 are localized to the cytosol. Based on these observations, the likely phylogenetic origin and the physiological significance of the cytosolic soluble pyrophosphatases are discussed.
Rojas-Beltrán
J A
JA
Unité de Biologie Végétale, Faculté Universitaire des Sciences Agronomiques de Gembloux, Belgium.
Dubois
F
F
Mortiaux
F
F
Portetelle
D
D
Gebhardt
C
C
Sangwan
R S
RS
du Jardin
P
P
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000378:metabolism; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D003600:Cytosol / Q000201:enzymology; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D043564:Inorganic Pyrophosphatase; D007527:Isoenzymes / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D008274:Magnesium / Q000494:pharmacology; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000276:immunology; D012150:Polymorphism, Restriction Fragment Length; D011755:Pyrophosphatases / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D011198:Solanum tuberosum / Q000737:chemistry / Q000201:enzymology / Q000235:genetics*; D012995:Solubility; D014018:Tissue Distribution
D000911:Antibodies, Monoclonal; D018076:DNA, Complementary; D007527:Isoenzymes; D010940:Plant Proteins; D011755:Pyrophosphatases; D043564:Inorganic Pyrophosphatase; D008274:Magnesium