A putative novel transcription factor, AtSKIP, is involved in abscisic acid signalling and confers salt and osmotic tolerance in Arabidopsis.
We identified and functionally characterized the AtSKIP gene (At1g77180), an Arabidopsis homologue of SNW/SKIP, under abiotic stresses. Although the SNW/SKIP protein has been implicated as a critical transcription cofactor, its biological functions have yet to be reported in any plant. Recently, we have isolated Salt-tolerance genes (SATs) via the overexpression screening of yeast with a maize cDNA library. One of the selected genes (SAT2) appeared to confer elevated tolerance to salt. Maize SAT2 cDNA encodes a homologue of the human SNW/SKIP transcriptional coregulator. Treatment with salt, mannitol and abscisic acid induced AtSKIP expression. Ectopic expression of the AtSKIP gene modulated the induction of salt tolerance, dehydration resistance and insensitivity towards abscisic acid under stress conditions. By contrast, atskip antisense lines displayed reduced tolerance to abiotic stresses during germination. Moreover, a decrease in AtSKIP expression resulted in an abnormal phenotype. We further determined that the AtSKIP protein activated the transcription of a reporter gene in yeast. Green fluorescent protein-tagged AtSKIP was localized in the nuclei of both onion cells and transgenic Arabidopsis cells. Taken together, these results suggest that AtSKIP functions as both a positive regulator and putative potential transcription factor in the abiotic stress signalling pathway.
Lim
Gah-Hyun
GH
Department of Plant Biotechnology and Agricultural Plant Stress Research Center, Chonnam National University, Gwangju 500-757, South Korea.
Zhang
Xia
X
Chung
Moon-Soo
MS
Lee
Dong Ju
DJ
Woo
Young-Min
YM
Cheong
Hyeon-Sook
HS
Kim
Cheol Soo
CS
D000040:Abscisic Acid / Q000235:genetics* / Q000502:physiology; D000123:Acetyltransferases / Q000235:genetics; D000222:Adaptation, Physiological / Q000235:genetics*; D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018076:DNA, Complementary; D003681:Dehydration; D018506:Gene Expression Regulation, Plant; D015723:Gene Library; D017343:Genes, Plant; D017930:Genes, Reporter; D018525:Germination; D006801:Humans; D008353:Mannitol; D009154:Mutation; D019697:Onions; D009995:Osmosis; D010641:Phenotype; D030821:Plants, Genetically Modified; D055049:Salt Tolerance / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics*; D012965:Sodium Chloride; D013312:Stress, Physiological / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015003:Yeasts / Q000235:genetics; D003313:Zea mays / Q000235:genetics
D029681:Arabidopsis Proteins; D018076:DNA, Complementary; C549998:SKIP protein, Arabidopsis; D014157:Transcription Factors; D008353:Mannitol; D012965:Sodium Chloride; D000040:Abscisic Acid; D000123:Acetyltransferases