A Role for PICKLE in the Regulation of Cold and Salt Stress Tolerance in Arabidopsis

Abstract

Arabidopsis PICKLE (PKL) is a putative CHD3-type chromatin remodeling factor with important roles in regulating plant growth and development as well as RNA-directed DNA methylation (RdDM). The role of PKL protein in plant abiotic stress response is still poorly understood. Here, we report that PKL is important for cold stress response in Arabidopsis. Loss-of-function mutations in the PKL gene lead to a chlorotic phenotype in seedlings under cold stress, which is caused by the alterations in the transcript levels of some chlorophyll metabolism-related genes. The pkl mutant also exhibits increased electrolyte leakage after freezing treatment. These results suggest that PKL is required for proper chilling and freezing tolerance in plants. Gene expression analysis shows that CBF3 , encoding a key transcription factor involved in the regulation of cold-responsive genes, exhibits an altered transcript level in the pkl mutant under cold stress. Transcriptome data also show that PKL regulates the expression of a number of cold-responsive genes, including RD29A, COR15A , and COR15B , possibly through its effect on the expression of CBF3 gene. Mutation in PKL gene also results in decreased cotyledon greening rate and reduced primary root elongation under high salinity. Together, our results suggest that PKL regulates plant responses to cold and salt stress.

Epigenetic regulation in plant abiotic stress responses

“…A recent study indicated that the chromatin remodeler PICKLE (PKL) participates in the CBF‐dependent cold stress response in Arabidopsis . The Arabidopsis pkl mutants are hypersensitive to chilling and cold stress treatments (Yang et al 2019). The expression of the transcription factor gene CBF3 and of downstream COR family genes such as COR15B and RESPONSIVE TO DEHYDRATION 29A ( RD29A) was downregulated in the pkl mutants after 3 h of cold treatment compared to that in wild‐type plants.…”

Insight into the Role of Epigenetic Processes in Abiotic and Biotic Stress Response in Wheat and Barley

“…Besides DNA methylation and histone modifications, chromatin structure and gene expression may also be affected by chromatin remodeling, a process that disrupts histone-DNA interactions resulting in the altered accessibility of specific DNA regions to transcription machinery [79,80]. Chromatin remodeling factor (CHR), including the SWI/SNF ATPases, the imitation switch (ISWI) ATPases, and the chromodomain and helicase-like domain (CHD) ATPases subfamilies, could mediate either the ATP-dependent chromatin remodeling or the posttranslational histone modifications [57,58,[73][74][75][76][77][78][79][80][81][82][83][84]. The ATP-dependent chromatin remodeling complexes could alter nucleosome composition, and positioning and thus regulate DNA accessibility and gene expression.…”

A Chloroplast COR413 Protein From Physcomitrella patens Is Required for Growth Regulation Under High Light and ABA Responses

“…In Arabidopsis, mutations in some genes involved in the regulation of COR gene expression, have been shown to exhibit ABA hypersensitive phenotypes (Perruc et al, 2007;Belin and Lopez-Molina, 2008;Kang et al, 2018). An example of such a regulatory gene is PKL, a putative CHD3-type chromatin remodeling factor with important roles in plant growth and development and responses to abiotic stress (Yang et al, 2017(Yang et al, , 2019. This indicates that, at least some COR proteins have regulatory roles in ABA-dependent responses.…”