Overexpression of the rice basic leucine zipper transcription factor OsbZIP12 confers drought tolerance to rice and makes seedlings hypersensitive to ABA

Abstract

Abiotic stresses such as drought, high salinity, and cold are key factors in determining crop yield. Rice is a notoriously drought-susceptible crop due in part to its small root system. Abscisic acid (ABA) involves in abiotic stress resistance in plants. The basic leucine zipper (bZIP) transcription factors play important roles in the ABA signaling pathway in plants. OsbZIP12 is a member of the group E bZIP transcription factor family in rice (Oryza sativa). Expression of OsbZIP12 is induced by abiotic stresses and ABA as well as sugar in rice. It is rapidly and strongly induced by drought stress. Corresponding with expression patterns, several stress and sugar-associated cis-acting elements were found in the OsbZIP12 promoter region. Transgenic rice overexpressing OsbZIP12 showed significantly improved drought tolerance and hypersensitivity to ABA. The elevated levels of expression of the ABA responding LEA3 and Rab16 genes in transgenic rice may enhance drought tolerance. These results indicate that OsbZIP12 is a positive regulator of ABA signaling and drought stress tolerance in rice and that OsbZIP12 could be involved in crosstalk among stress, hormone, and sugar signaling. We propose that OsbZIP12 is an important player in rice for conferring ABA-dependent drought tolerance and has high potential for use in the genetic improvement of stress tolerance.

Genome-wide identification, structural and gene expression analysis of the bZIP transcription factor family in sweet potato wild relative Ipomoea trifida

“…AtbZIP10-LSD1 regulates basic defence and cell death in Arabidopsis thaliana after infection [60]. In rice, OsbZIP12 is a positive regulator of ABA signalling, conferring ABA-dependent drought tolerance [61]. And OsbZIP23 and OsbZIP72 also increase drought resistance through the ABA pathway [29,62].…”

Transcriptional Network Involved in Drought Response and Adaptation in Cereals

“…These TFs are likely to bind to the corresponding cis-elements and co-regulate the expression of Os-NAC6 that participate in the ABA induction pathway and abiotic stress response in plants. In the bZIP family, the gene encoding OsbZIP12 was also found to have MYBRS, MYCRS, and W-box motifs in its promoter region, which can be recognized by TFs MYB, MYC, and WRKY, respectively [34]. Besides, OsNAC5 and OsbZip23 might co-regulate the expression of the downstream gene OsLEA3 since both of them enhance the transcription level of OsLEA3 [35].…”

“…In maize, ZmbZIP37, -17, and -112 showed high expression levels in drought stress conditions [88,89] and the overexpression of ZmbZIP72 enhanced the drought tolerance in transgenic Arabidopsis [90]. In rice, OsbZIP12 [34], -16 [91], -23, -45 [92], -71 [25], and -72 [93] play a positive role in drought tolerance through ABA signal, while OsbZIP52 [24] and -46 [94] were suggested to be a negative regulator in water deficiency. In wheat, the gene encoding TabZIP60 was highly induced by salt, cold, and ABA, and the overexpression of TabZIP60 enhanced the drought and frost tolerance in transgenic Arabidopsis [84].…”

Overexpression of the OsERF71 Transcription Factor Alters Rice Root Structure and Drought Resistance

“…Several studies have shown that overexpression of droughtresponsive transcription factors can lead to enhanced drought resistance. For example, plants overexpressing Arabidopsis (Arabidopsis thaliana) AtMYB96 or HARDY (an AP2/ERF transcription factor) or transgenic rice (Oryza sativa) lines overexpressing OsAP37, OsNAC5, OsNAC9, OsNAC10, OsbZIP12, OsbZIP12, or OsbZIP23 all showed strong resistance to drought stress (Karaba et al, 2007;Oh et al, 2009;Jeong et al, 2010Jeong et al, , 2013Seo et al, 2011;Redillas et al, 2012;Joo et al, 2014;Park et al, 2015). Drought-responsive genes are often categorized into abscisic acid (ABA)-dependent or ABAindependent groups.…”