Molecular and Physiological Characterization of the Arabidopsis thaliana Oxidation-Related Zinc Finger 2, a Plasma Membrane Protein Involved in ABA and Salt Stress Response Through the ABI2-Mediated Signaling Pathway

Abstract

CCCH-type zinc finger proteins are important for developmental and environmental responses. However, the precise roles of these proteins in plant stress tolerance are poorly understood. Arabidopsis thaliana Oxidation-related Zinc Finger 2 (AtOZF2) (At4g29190) is an AtOZF1 homolog previously isolated from Arabidopsis, which confers oxidative stress tolerance on plants. The AtOZF2 protein is localized in the plasma membrane, as is AtOZF1. Disruption expression of AtOZF2 led to reduced root length and leaf size. AtOZF2 was implicated to be involved in the ABA and salinity responses. atozf2 antisense lines were more sensitive to ABA and salt stress during the seed germination and cotyledon greening processes. In contrast, AtOZF2-overexpressing plants were more insensitive to ABA and salt stress than the wild type. Interestingly, in the presence of ABA and salt stress, the transcript level of ABA insensitive 2 (ABI2), but not that of ABI1, in AtOZF2-overexpressing plants was lower than that in the wild type, whereas the expression of ABI2 in atozf2 was significantly enhanced. Thus, AtOZF2 is involved in the ABA and salt stress response through the ABI2-mediated signaling pathway. Taken together, these findings provide compelling evidence that AtOZF2 is an important regulator for plant tolerance to abiotic stress.

Moderate drought causes dramatic floral transcriptomic reprogramming to ensure successful reproductive development in Arabidopsis

“…The OZFs are the closely related with two CCCH motifs [38]. Both OZF factors are ABA-responsive and OZF2 is involved in the ABI2-mediated signaling pathway [39,40]. It is possible that the two OZF function redundantly to assist the plant in response to various stresses.…”

Regulation of mRNA decay in plant responses to salt and osmotic stress

“…Overexpression lines of TZF2 and TZF3 showed higher drought tolerance and reduced water loss than wild type plants [91]. Moreover, induction of TZF3 resulted in decreased expression of ABI2, while a tzf3 knock-out mutant was hypersensitive to both salt stress and ABA [94]. Rice OsTZF1 relocalised to P bodies upon salt stress or ABA treatment and its overexpression conferred faster recovery from salinity or drought [89].…”

“…Similar to mammalian TZFs, plant TZFs can shuttle between nucleus and cytoplasm and localize to P bodies and stress granules [89, 90, 95, 96]. Importantly, altered expression of TZFs affects usually a subset of transcripts [91, 93, 94]. Specificity of mRNA metabolism processes that occur in P bodies may rely on TZF proteins binding to cis-elements in mRNA [17].…”

Characterization of OsPM19L1 encoding an AWPM-19-like family protein that is dramatically induced by osmotic stress in rice

“…ABA serves as an endogenous signal to initiate the adaptive responses when plants are challenged by abiotic or biotic stress (Zhu, 2002;Adie et al, 2007;Bari and Jones, 2009;Huang et al, 2012a;Ye et al, 2012;Nakashima and YamaguchiShinozaki, 2013;Danquah et al, 2014;Mehrotra et al, 2014). It has been established that two distinct pathways (ABA dependent and ABA independent) are involved in stress-responsive gene expression (Huang et al, 2012b;Yoshida et al, 2014). Previous research has helped to identify the key components of ABA signaling.…”