Expression profiling and bioinformatic analyses of a novel stress-regulated multispanning transmembrane protein family from cereals and Arabidopsis.
Cold acclimation is a multigenic trait that allows hardy plants to develop efficient tolerance mechanisms needed for winter survival. To determine the genetic nature of these mechanisms, several cold-responsive genes of unknown function were identified from cold-acclimated wheat (Triticum aestivum). To identify the putative functions and structural features of these new genes, integrated genomic approaches of data mining, expression profiling, and bioinformatic predictions were used. The analyses revealed that one of these genes is a member of a small family that encodes two distinct groups of multispanning transmembrane proteins. The cold-regulated (COR)413-plasma membrane and COR413-thylakoid membrane groups are potentially targeted to the plasma membrane and thylakoid membrane, respectively. Further sequence analysis of the two groups from different plant species revealed the presence of a highly conserved phosphorylation site and a glycosylphosphatidylinositol-anchoring site at the C-terminal end. No homologous sequences were found in other organisms suggesting that this family is specific to the plant kingdom. Intraspecies and interspecies comparative gene expression profiling shows that the expression of this gene family is correlated with the development of freezing tolerance in cereals and Arabidopsis. In addition, several members of the family are regulated by water stress, light, and abscisic acid. Structure predictions and comparative genome analyses allow us to propose that the cor413 genes encode putative G-protein-coupled receptors.
Breton
Ghislain
G
Département des Sciences biologiques, Université du Québec à Montréal, Case Postale 8888, succursale Centre-ville, Canada H3C 3P8.
Danyluk
Jean
J
Charron
Jean-Benoît Frenette
JB
Sarhan
Fathey
F
D000064:Acclimatization / Q000235:genetics* / Q000502:physiology; D017360:Arabidopsis / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics; D002462:Cell Membrane / Q000378:metabolism; D003080:Cold Temperature; D019295:Computational Biology; D020869:Gene Expression Profiling / Q000379:methods*; D018506:Gene Expression Regulation, Plant / Q000528:radiation effects; D017261:Glycosylphosphatidylinositols / Q000235:genetics / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D008027:Light; D008565:Membrane Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics; D010766:Phosphorylation; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D020524:Thylakoids / Q000378:metabolism; D014908:Triticum / Q000235:genetics*
D029681:Arabidopsis Proteins; C095314:COR14 protein, Triticum aestivum; D017261:Glycosylphosphatidylinositols; D006360:Heat-Shock Proteins; D008565:Membrane Proteins; D010940:Plant Proteins