Cloning and characterisation of PGA1 and PGA2: two G protein alpha-subunits from pea that promote growth in the yeast Saccharomyces cerevisiae.
We report here on the cloning and characterization of two G protein alpha-subunits from pea: PGA1 and PGA2. Based on DNA gel blot analysis, PGA1 and PGA2 are the only Galpha homologous sequences in pea. RT-PCR analysis reveals that PGA1 and PGA2 transcripts are present in a variety of adult pea tissues. However, PGA2 mRNA is consistently detected at a lower level than PGA1 and demonstrates some degree of tissue specificity relative to PGA1. In the apical bud of pea seedlings, PGA1 and PGA2 transcripts decrease in response to 24 h of white light following growth for 6 days in darkness. The G protein mediated, yeast mating pathway was used to analyse the function of PGA1 and PGA2 in vivo. PGA1 downregulates the mating pathway, but through a mechanism that is independent of Gbetagamma sequestration. Unexpectedly, both PGA1 and PGA2 promote growth through a mating pathway independent mechanism.
Marsh
J F
JF
Department of Biological Sciences, University of Illinois at Chicago, 60607, USA.
Kaufman
L S
LS
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics; D019204:GTP-Binding Proteins / Q000737:chemistry / Q000235:genetics*; D015870:Gene Expression; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D018532:Pisum sativum / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D010675:Pheromones / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics*; D011401:Promoter Regions, Genetic; D011487:Protein Conformation; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development*; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid
D017931:DNA Primers; C490024:FUS1 protein, S cerevisiae; D005656:Fungal Proteins; D008565:Membrane Proteins; D010675:Pheromones; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D029701:Saccharomyces cerevisiae Proteins; D019204:GTP-Binding Proteins