Characterization of Arabidopsis thaliana GCN2 kinase roles in seed germination and plant development.
Eukaryotic GCN2 (general control nonderepressible 2) is a serine/threonine protein kinase that plays an essential role in modulating amino acid metabolism in response to nutrient deprivation. A wide spectrum of GCN2 functions in yeast and mammals has been characterized that spans from responses to amino acid deficiency, development, differentiation and proper functions of mammalian organs to organism's life span, tumor cell survival and immune responses. Here we demonstrate that Arabidopsis thaliana GCN2 (AtGCN2) plays crucial roles in plant growth and development. We present evidence that AtGCN2 negatively regulates seed germination under diverse environmental conditions. Our genetic data supported the notion that AtGCN2 is required for leaf morphology and normal cellular physiology by controlling chlorophyll contents. Our gene expression analyses revealed that AtGCN2 negatively regulates several transcription factor genes that play important roles in plant gibberellic acid-related crosstalk. We concluded that AtGCN2 plays pivotal roles in various cellular processes essential for normal growth and development, hence expanding the functions of this general regulator beyond being merely a stress player.
a Department of Biology ; University of Alabama at Birmingham ; Birmingham , AL USA.
Xiaoyu
X
Liu
Azim
A
Merchant
Kristin S
KS
Rockett
Maggie
M
McCormack
Karolina M
KM
Pajerowska-Mukhtar
D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002734:Chlorophyll / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects; D005875:Gibberellins / Q000494:pharmacology; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D010858:Pigmentation / Q000187:drug effects; D018515:Plant Leaves / Q000033:anatomy & histology / Q000187:drug effects; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development*
D029681:Arabidopsis Proteins; D005875:Gibberellins; D012333:RNA, Messenger; D002734:Chlorophyll; C007842:gibberellic acid; D011494:Protein Kinases; C480318:GCN2 protein, Arabidopsis
AtGCN2; CGA1; GNC; chlorophyll; germination; gibberellin; leaf development; translational control