Isolation and characterization of maize ZmPP2C26 gene promoter in drought-response

Abstract

The clade A members of serine/threonine protein phosphatase 2Cs (PP2Cs) play crucial roles in plant growth, development, and stress response via the ABA signaling pathway. But little is known about other PP2C clades in plants. Our previous study showed that maize the ZmPP2C26, a clade B member of ZmPP2Cs, negatively regulated drought tolerance in transgenic Arabidopsis. However, the upstream regulatory mechanism of ZmPP2C26 remains unclear. In the present study, the expression of ZmPP2C26 gene in maize was analyzed by quantitative real time PCR (qRT-PCR). The results showed that the expression of ZmPP2C26 in shoot and root was both significantly inhibited by drought stress. Subsequently, a 2175 bp promoter of ZmPP2C26 was isolated from maize genome (P 2175 ). To validate whether the promoter possess some key cis-element and negatively drive ZmPP2C26 expression in drought stress, three 5-deletion fragments of 1505, 1084 and 215 bp was amplified from P 2175 and were fused to b-glucuronidase (GUS) and luciferase gene (LUC) to produce promoter::GUS and promoter::LUC constructs, and transformed into tobacco, respectively. Transient expression assays indicated that all promoters could drive GUS and LUC expression. The GUS and LUC activity were both significantly inhibited by PEG-6000 treatment. Notably, the -1084 to -215 bp promoter possess one MBS element and inhibits the expression of GUS and LUC under drought stress. Meanwhile, we found that the 215 bp length is enough to drive ZmPP2C26 expression. These findings will provide insights into understanding the transcription-regulatory mechanism of ZmPP2C26 negatively regulating drought tolerance.

Transcriptome-wide identification of walnut PP2C family genes in response to external stimulus

“…The PP2C gene family is one of the largest families of plant and has been identified as important members playing crucial roles in phytohormone signaling, developmental processes, biotic and abiotic stress responses [8,17,36], however, PP2C genes from walnut trees was still not reported. In order to reveal the adversity adaptation mechanism of walnuts then to provide a basis for walnut cultivation and management to ensure the yield and quality, in this study, 41 walnut PP2C genes those may have potential functions in stress response were identified (Table 1).…”

“…PeHAB1 could interact with the ABA receptor PYL4 in an ABA-independent manner to reduce tolerance to drought in poplar [16]. In maize, ZmPP2C26 has a negative regulatory effect against drought stress [17]. Tomato SlPP2C gene family that encoding the core component of ABA signaling could regulate tomato fruit development and be induced by drought [18].…”

The battle of crops against drought: Genetic dissection and improvement

“…ZmPP2C26 negatively regulates drought tolerance by dephosphorylating mitogenactivated protein kinases (ZmMAPK3 and ZmMAPK7). Yeast two-hybrid screening showed that ZmPP2C26 interacts with ZmMAPK but not ZmPYLs, confirming the role of ZmPP2C26 in MAPK signaling (Lu et al, 2020(Lu et al, , 2022. However, the roles of ZmMAPK3 and ZmMAPK7 in the response of maize to drought stress require further study.…”

Genome-wide identification of Aux/IAA gene family in white clover (Trifolium repens L.) and functional verification of TrIAA18 under different abiotic stress

“…In this study, most TrIAA gene promoters contained growth hormone-responsive (AuxRE/TGA-element) cis-elements or their variants [ 50 ]. Some TrIAA gene promoters have been reported to contain cis-elements involved in abiotic stress response, for example, LTR is involved in low temperature response [ 51 ], MBS plays a role in drought- inducibility [ 52 , 53 ], ARE is involved in anaerobic induction, and TC_rich_repeats are involved in defense and stress response [ 54 ]. In conclusion, the different types of cis-elements on the promoters of the TrIAA gene family reflect the complexity and diversity of gene expression regulation and evolution.…”