LOS2, a genetic locus required for cold-responsive gene transcription encodes a bi-functional enolase.
The Arabidopsis mutation, los2, impairs cold-responsive gene transcription, acquired freezing tolerance and plant resistance to chilling under certain conditions. LOS2 was isolated through positional cloning and shown to encode an enolase in the glycolytic pathway. In animal cells, enolase has also been known to function as a transcription factor that represses the expression of c-myc by binding to the c-myc gene promoter. LOS2 fused to green fluorescent protein is targeted to the nucleus as well as to the cytoplasm. LOS2/enolase protein can bind to the cis-element of the human c-myc gene promoter and to the gene promoter of STZ/ZAT10, a zinc finger transcriptional repressor from Arabidopsis. STZ/ZAT10 expression is induced rapidly and transiently by cold in the wild type, and this induction is stronger and more sustained in the los2 mutant. Furthermore, the expression of a RD29A-LUC reporter gene is repressed significantly by STZ/ZAT10 in transient expression assays in Arabidopsis leaves. Our results demonstrate that cold-responsive gene transcription in plants is controlled by a bi-functional enolase.
Lee
Hojoung
H
Department of Plant Sciences, University of Arizona, Tucson, AZ 85721, USA.
Guo
Yan
Y
Ohta
Masaru
M
Xiong
Liming
L
Stevenson
Becky
B
Zhu
Jian-Kang
JK
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D003080:Cold Temperature; D003593:Cytoplasm / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D005615:Freezing; D005816:Genetic Complementation Test; D049452:Green Fluorescent Proteins; D006358:Hot Temperature; D015151:Immunoblotting; D008027:Light; D008164:Luminescent Proteins / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009154:Mutation; D010751:Phosphopyruvate Hydratase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011110:Polymorphism, Genetic; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012313:RNA / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013696:Temperature; D013997:Time Factors; D014158:Transcription, Genetic; D016335:Zinc Fingers
D008164:Luminescent Proteins; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D012313:RNA; D004247:DNA; D010751:Phosphopyruvate Hydratase