Snf1-related protein kinase 1 is needed for growth in a normal day-night light cycle.
The yeast Snf1 protein kinase and its animal homologue, the AMP-activated protein kinase, play important roles in metabolic regulation, by serving as energy gauges that turn off energy-consuming processes and mobilize energy reserves during low-energy conditions. The closest homologue of these kinases in plants is Snf1-related protein kinase 1 (SnRK1). We have cloned two SnRK1-encoding genes, PpSNF1a and PpSNF1b, in the moss Physcomitrella patens, where gene function can be studied directly by gene targeting in the haploid gametophyte. A snf1a snf1b double knockout mutant is viable, but lacks all Snf1-like protein kinase activity. The mutant has a complex phenotype that includes developmental abnormalities, premature senescence and altered sensitivities to plant hormones. Remarkably, the double knockout mutant also requires continuous light, and is unable to grow in a normal day-night light cycle. This suggests that SnRK1 is needed for metabolic changes that help the plant cope with the dark hours of the night.
Thelander
Mattias
M
Department of Plant Biology and Forest Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Olsson
Tina
T
Ronne
Hans
H
D055372:AMP-Activated Protein Kinases; D019068:Bryopsida / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development* / Q000528:radiation effects*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D016922:Cellular Senescence; D003583:Cytokinins / Q000494:pharmacology; D003624:Darkness; D015870:Gene Expression; D018390:Gene Targeting; D005816:Genetic Complementation Test; D006801:Humans; D007210:Indoleacetic Acids / Q000494:pharmacology; D008027:Light; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D010802:Phylogeny; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D013213:Starch / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
D002352:Carrier Proteins; D003583:Cytokinins; D007210:Indoleacetic Acids; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D013213:Starch; C071570:SNF1-related protein kinases; D017346:Protein Serine-Threonine Kinases; C078651:SNF4 protein, S cerevisiae; D055372:AMP-Activated Protein Kinases