A polyadenylation factor subunit implicated in regulating oxidative signaling in Arabidopsis thaliana.
BACKGROUND
Plants respond to many unfavorable environmental conditions via signaling mediated by altered levels of various reactive oxygen species (ROS). To gain additional insight into oxidative signaling responses, Arabidopsis mutants that exhibited tolerance to oxidative stress were isolated. We describe herein the isolation and characterization of one such mutant, oxt6.


RESULTS
The oxt6 mutation is due to the disruption of a complex gene (At1g30460) that encodes the Arabidopsis ortholog of the 30-kD subunit of the cleavage and polyadenylation specificity factor (CPSF30) as well as a larger, related 65-kD protein. Expression of mRNAs encoding Arabidopsis CPSF30 alone was able to restore wild-type growth and stress susceptibility to the oxt6 mutant. Transcriptional profiling and single gene expression studies show elevated constitutive expression of a subset of genes that encode proteins containing thioredoxin- and glutaredoxin-related domains in the oxt6 mutant, suggesting that stress can be ameliorated by these gene classes. Bulk poly(A) tail length was not seemingly affected in the oxt6 mutant, but poly(A) site selection was different, indicating a subtle effect on polyadenylation in the mutant.


CONCLUSIONS
These results implicate the Arabidopsis CPSF30 protein in the posttranscriptional control of the responses of plants to stress, and in particular to the expression of a set of genes that suffices to confer tolerance to oxidative stress.
Kentucky Tobacco Research and Development Center, University of Kentucky, Lexington, Kentucky, United States of America.
Jingxian
J
Zhang
Balasubramanyam
B
Addepalli
Kil-Young
KY
Yun
Arthur G
AG
Hunt
Ruqiang
R
Xu
Suryadevara
S
Rao
Qingshun Q
QQ
Li
Deane L
DL
Falcone
D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000378:metabolism; D039223:Cleavage And Polyadenylation Specificity Factor / Q000737:chemistry / Q000378:metabolism; D020869:Gene Expression Profiling; D005816:Genetic Complementation Test; D018384:Oxidative Stress; D016133:Polymerase Chain Reaction; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction; D039221:mRNA Cleavage and Polyadenylation Factors / Q000737:chemistry / Q000378:metabolism*
D029681:Arabidopsis Proteins; C521936:CPSF30 protein, Arabidopsis; D039223:Cleavage And Polyadenylation Specificity Factor; D017382:Reactive Oxygen Species; D039221:mRNA Cleavage and Polyadenylation Factors