TY - JOUR
T1 - A DEAD Box RNA Helicase Is Essential for mRNA Export and Important for Development and Stress Responses in Arabidopsis
AU - Gong, Zhizhong
AU - Dong, Chun Hai
AU - Lee, Hojoung
AU - Zhu, Jianhua
AU - Xiong, Liming
AU - Gong, Deming
AU - Stevenson, Becky
AU - Zhu, Jian Kang
N1 - Funding information:
This work was supported by USDA National Research Initiative Grant 2003-00751 (J.-K.Z.), National Science Foundation Grants IBN-0212346 and MCB-0241450 (J.-K.Z.), National Research Program of China Grant 2003CB114300 (Z.G.), and National High Technology Research and Development Program of China Grant 2003AA222121 (Z.G.).
Publisher copyright:
© 2005 American Society of Plant Biologists
PY - 2005/1
Y1 - 2005/1
N2 - An Arabidopsis thaliana mutant, cryophyte, was isolated and found to have an enhanced cold stress-induction of the master regulator of cold tolerance, C-repeat binding factor 2 (CBF2), and its downstream target genes. The mutant is more tolerant to chilling and freezing stresses but is more sensitive to heat stress. Under warm but not cold growth temperatures, the mutant has a reduced stature and flowers earlier. Under long day conditions, flowering of the mutant is insensitive to vernalization. The mutant is also hypersensitive to the phytohormone abscisic acid. The mutation was found in a DEAD box RNA helicase gene that is identical to the previously identified low expression of osmotically responsive genes 4 (LOS4) locus, which was defined by the los4-1 mutation that reduces cold regulation of CBFs and their target genes and renders Arabidopsis plants chilling sensitive. We show evidence suggesting that the CRYOPHYTE/LOS4 protein may be enriched in the nuclear rim. In situ poly(A) hybridization indicates that the export of poly(A)+ RNAs is blocked in the cryophyte/los4-2 mutant at warm or high temperatures but not at low temperatures, whereas the los4-1 mutation weakens mRNA export at both low and warm temperatures. These results demonstrate an important role of the CRYOPHYTE/LOS4 RNA helicase in mRNA export, plant development, and stress responses.
AB - An Arabidopsis thaliana mutant, cryophyte, was isolated and found to have an enhanced cold stress-induction of the master regulator of cold tolerance, C-repeat binding factor 2 (CBF2), and its downstream target genes. The mutant is more tolerant to chilling and freezing stresses but is more sensitive to heat stress. Under warm but not cold growth temperatures, the mutant has a reduced stature and flowers earlier. Under long day conditions, flowering of the mutant is insensitive to vernalization. The mutant is also hypersensitive to the phytohormone abscisic acid. The mutation was found in a DEAD box RNA helicase gene that is identical to the previously identified low expression of osmotically responsive genes 4 (LOS4) locus, which was defined by the los4-1 mutation that reduces cold regulation of CBFs and their target genes and renders Arabidopsis plants chilling sensitive. We show evidence suggesting that the CRYOPHYTE/LOS4 protein may be enriched in the nuclear rim. In situ poly(A) hybridization indicates that the export of poly(A)+ RNAs is blocked in the cryophyte/los4-2 mutant at warm or high temperatures but not at low temperatures, whereas the los4-1 mutation weakens mRNA export at both low and warm temperatures. These results demonstrate an important role of the CRYOPHYTE/LOS4 RNA helicase in mRNA export, plant development, and stress responses.
UR - http://www.scopus.com/inward/record.url?scp=21444454906&partnerID=8YFLogxK
U2 - 10.1105/tpc.104.027557
DO - 10.1105/tpc.104.027557
M3 - Journal article
C2 - 15598798
AN - SCOPUS:21444454906
SN - 1040-4651
VL - 17
SP - 256
EP - 267
JO - Plant Cell
JF - Plant Cell
IS - 1
ER -