Overexpression of soybean ubiquitin-conjugating enzyme gene GmUBC2 confers enhanced drought and salt tolerance through modulating abiotic stress-responsive gene expression in Arabidopsis.
Previous studies have shown that ubiquitination plays important roles in plant abiotic stress responses. In the present study, the ubiquitin-conjugating enzyme gene GmUBC2, a homologue of yeast RAD6, was cloned from soybean and functionally characterized. GmUBC2 was expressed in all tissues in soybean and was up-regulated by drought and salt stress. Arabidopsis plants overexpressing GmUBC2 were more tolerant to salinity and drought stresses compared with the control plants. Through expression analyses of putative downstream genes in the transgenic plants, we found that the expression levels of two ion antiporter genes AtNHX1 and AtCLCa, a key gene involved in the biosynthesis of proline, AtP5CS, and the copper chaperone for superoxide dismutase gene AtCCS, were all increased significantly in the transgenic plants. These results suggest that GmUBC2 is involved in the regulation of ion homeostasis, osmolyte synthesis, and oxidative stress responses. Our results also suggest that modulation of the ubiquitination pathway could be an effective means of improving salt and drought tolerance in plants through genetic engineering.
Zhou
Guo-An
GA
The National Key Facility for Crop Gene Resources and Genetic Improvement (NFCRI)/Key Lab of Germplasm Utilization (MOA), Institute of Crop Science, Chinese Academy of Agricultural Sciences, 100081 Beijing, China. guoanzhou2001@yahoo.com.cn
Chang
Ru-Zhen
RZ
Qiu
Li-Juan
LJ
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D027682:Cation Transport Proteins / Q000235:genetics / Q000378:metabolism; D018118:Chloride Channels / Q000235:genetics / Q000378:metabolism; D017931:DNA Primers / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D055864:Droughts; D015870:Gene Expression; D017343:Genes, Plant; D005818:Genetic Engineering; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010802:Phylogeny; D030821:Plants, Genetically Modified; D011188:Potassium / Q000378:metabolism; D011392:Proline / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D054712:Salinity; D017386:Sequence Homology, Amino Acid; D012964:Sodium / Q000378:metabolism; D017923:Sodium-Hydrogen Exchangers / Q000235:genetics / Q000378:metabolism; D013025:Glycine max / Q000201:enzymology* / Q000235:genetics*; D013312:Stress, Physiological; D013482:Superoxide Dismutase / Q000378:metabolism; D044763:Ubiquitin-Conjugating Enzymes / Q000235:genetics* / Q000378:metabolism*
C407524:ATCLC-A protein, Arabidopsis; D029681:Arabidopsis Proteins; D027682:Cation Transport Proteins; D018118:Chloride Channels; D017931:DNA Primers; D018744:DNA, Plant; C117751:NHX1 protein, Arabidopsis; D011993:Recombinant Fusion Proteins; D017923:Sodium-Hydrogen Exchangers; C485184:enhanced green fluorescent protein; D049452:Green Fluorescent Proteins; D011392:Proline; D012964:Sodium; D013482:Superoxide Dismutase; D044763:Ubiquitin-Conjugating Enzymes; D011188:Potassium