Arabidopsis CCoAOMT1 Plays a Role in Drought Stress Response via ROS- and ABA-Dependent Manners

Abstract

Plants possess adaptive reprogramed modules to prolonged environmental stresses, including adjustment of metabolism and gene expression for physiological and morphological adaptation. CCoAOMT1 encodes a caffeoyl CoA O-methyltransferase and is known to play an important role in adaptation of Arabidopsis plants to prolonged saline stress. In this study, we showed that the CCoAOMT1 gene plays a role in drought stress response. Transcript of CCoAOMT1 was induced by salt, dehydration (drought), and methyl viologen (MV), and loss of function mutants of CCoAOMT1, ccoaomt1-1, and ccoaomt1-2 exhibit hypersensitive phenotypes to drought and MV stresses. The ccoaomt1 mutants accumulated higher level of H2O2 in the leaves and expressed lower levels of drought-responsive genes including RD29B, RD20, RD29A, and ERD1, as well as ABA3 3 and NCED3 encoding ABA biosynthesis enzymes during drought stress compared to wild-type plants. A seed germination assay of ccoaomt1 mutants in the presence of ABA also revealed that CCoAOMT1 functions in ABA response. Our data suggests that CCoAOMT1 plays a positive role in response to drought stress response by regulating H2O2 accumulation and ABA signaling.

Quantitative Time-Course Analysis of Osmotic and Salt Stress inArabidopsis thalianausing Short Gradient Multi-CV FAIMSpro BoxCar DIA

“…Here we see that osmotic stress up-regulates a set of phenylpropanoid biosynthetic proteins, including: PHENYLALANINE AMMONIA-LYASE 4 (PAL4; AT3G10340), 4-COUMARATE-CoA LIGASE (4CL1; AT1G51680, 4CL2; AT3G21240 & 4CL5; AT3G21230), and CAFFEOYL-CoA 3-O-METHYLTRANSFERASE (CCoAOMT1; AT4G34050) (98). Among these, expression of CCoAOMT1 was found to be induced by both mannitol and salt treatments (99, 100), while our data shows a similar increase in CCoAOMT1 protein levels in response to osmotic stress. Additionally, PAL proteins are responsible for catalyzing the first step of phenylpropanoid pathway and responding to environmental stress (101), with PAL1 and 2 proposed to be the principal functional isoforms in plants (98, 102).…”

Stimulation of Tomato Drought Tolerance by PHYTOCHROME A and B1B2 Mutations

“…The expression of DREB2 was significantly lower in both phyA and phyB1B2 mutants than that in the WT plants under drought conditions, without any marked difference under control conditions ( Figure 5 a). Moreover, the expression levels of RESPONSIVE TO DESICCATION 29A ( RD29A ) and RD29B, which are dehydration-responsive genes that enhance drought tolerance [ 40 ], under control conditions were higher in the phyA mutant than that in the WT and phyB1B2 mutant, without a significant difference between the latter two. In addition to RD29A and RD29B , the expression of EARLY RESPONSIVE TO DEHYDRATION 1 ( ERD1 ), which is also a dehydration-responsive gene that enhances drought tolerance [ 40 ], was not significant in either phy mutant compared to the WT under non-stress conditions.…”

“…Moreover, the expression levels of RESPONSIVE TO DESICCATION 29A ( RD29A ) and RD29B, which are dehydration-responsive genes that enhance drought tolerance [ 40 ], under control conditions were higher in the phyA mutant than that in the WT and phyB1B2 mutant, without a significant difference between the latter two. In addition to RD29A and RD29B , the expression of EARLY RESPONSIVE TO DEHYDRATION 1 ( ERD1 ), which is also a dehydration-responsive gene that enhances drought tolerance [ 40 ], was not significant in either phy mutant compared to the WT under non-stress conditions. In contrast, the expression level of these genes was markedly lower in phyA and phyB1B2 mutants than that in the WT plants under drought conditions ( Figure 5 a).…”

Microtubule Dynamics Plays a Vital Role in Plant Adaptation and Tolerance to Salt Stress

“…CCoAOMT1 (AT4G34050), encoding caffeoyl-coA o-methyltransferase 1, plays an essential role in lignin biosynthesis and salt stress response [ 60 ]. ccoaomt1 mutants showed a hypersensitive phenotype to salt and drought stresses [ 60 , 61 ]. SAHH1 (AT4G13940), encoding S-adenosyl-L-homocysteine hydrolase 1, is involved in the interaction between cytokinin and DNA methylation.…”