A DEAD Box RNA Helicase Is Critical for Pre-mRNA Splicing, Cold-Responsive Gene Regulation, and Cold Tolerance inArabidopsis   

Abstract

Cold stress resulting from chilling and freezing temperatures substantially reduces crop production worldwide. To identify genes critical for cold tolerance in plants, we screened Arabidopsis thaliana mutants for deregulated expression of a firefly luciferase reporter gene under the control of the C-REPEAT BINDING FACTOR2 (CBF2) promoter (CBF2:LUC). A regulator of CBF gene expression1 (rcf1-1) mutant that is hypersensitive to cold stress was chosen for in-depth characterization. RCF1 encodes a cold-inducible DEAD (Asp-Glu-Ala-Asp) box RNA helicase. Unlike a previously reported DEAD box RNA helicase (LOW EXPRESSION OF OSMOTICALLY RESPONSIVE GENES4 [LOS4]) that regulates mRNA export, RCF1 does not play a role in mRNA export. Instead, RCF1 functions to maintain proper splicing of pre-mRNAs; many cold-responsive genes are misspliced in rcf1-1 mutant plants under cold stress. Functional characterization of four genes (PSEUDO-RESPONSE, and SPFH/PHB DOMAIN-CONTAINING MEMBRANE-ASSOCIATED PROTEIN [SPFH]) that are misspliced in rcf1-1 revealed that these genes are cold-inducible positive (CIR1 and SPFH) and negative (PRR5 and SK12) regulators of cold-responsive genes and cold tolerance. Together, our results suggest that the cold-inducible RNA helicase RCF1 is essential for pre-mRNA splicing and is important for cold-responsive gene regulation and cold tolerance in plants.

Alternative Splicing at the Intersection of Biological Timing, Development, and Stress Responses

“…The cold-inducible RNA helicase REGULA-TOR OF C-REPEAT BINDING FACTOR GENE EXPRESSION1 is essential for splicing and is important for cold-responsive gene expression and cold tolerance in Arabidopsis (Guan et al, 2013). PRMT5, a type II protein Arg methyltransferase that symmetrically dimethylates Arg side chains, also impacts splicing/AS in Arabidopsis.…”

DEAD-box RNA helicases and epigenetic control of abiotic stress-responsive gene expression

“…In plants, DEADbox RNA helicases have been associated with diverse molecular functions such as siRNA-mediated gene silencing, premRNA splicing, chloroplast/mitochondrial intron splicing, nonsense-mediated mRNA decay, mRNA export, ribosome biogenesis and exon-junction complex functions. [11][12][13][14][15][16][17][18][19][20][21][22] Furthermore, it has been shown that these helicases play roles in Keywords: abiotic stress, Arabidopsis thaliana, DEAD-box RNA helicases, epigenetic gene silencing, nucleolus, RNAdirected DNA methylation Abbreviations: ABA, abscisic acid; STRS, STRESS RESPONSE SUPPRESSOR; RdDM, RNA-directed DNA methylation. various biological processes including abiotic stress responses.…”

“…various biological processes including abiotic stress responses. 6,12,15,19,[23][24][25][26][27][28][29] To further explore the function of the STRS DEAD-box RNA helicases in regulating abiotic stress-responsive gene expression, we examined STRS sub-cellular localization.…”

Analysis of the role of RNS2 and autophagy in the turnover of ribosomal RNA in Arabidopsis thaliana

“…However, the DEVH-box helicase mutant, Athelps, had increased autophagy while the nucleoside phosphatase mutant did not. Combined with the important physiological roles that DEAD-box family helicases play in RNA mechanisms (Guan et al 2013;Tuteja et al 2014;Zhang et al 2014), as well as their RNA-binding and ATP hydrolysis ability ), I speculate that AtHELPS is involved in an RNautophagy-like process in plants.…”

“…AtHELPS seems to functions as a negative regulator during low potassium stress ). Other DEAD-box helicases have been implicated in a variety of physiological processes in plants including determination of cell fate, biotic and abiotic stress, gene silencing, and growth (Kobayashi et al 2007;Guan et al 2013;Gu et al 2014;Khan et al 2014;Tuteja et al 2014;Zhang et al 2014).…”