Root-derived long-distance signals trigger ABA synthesis and enhance drought resistance in Arabidopsis

Vascular plants have evolved intricate long-distance signaling mechanisms to cope with environmental stress,with reactive oxygen species(ROS)emerging as pivotal systemic signals in plant stress responses.However,the exact role of ROS as root-to-shoot signals in the drought response has not been determined.In this study,we reveal that compared with wild-type plants,ferric reductase defective 3(frd3)mutants exhibit enhanced drought resistance concomitant with elevated NINE-CIS-EPOXYCAROTENOID DIOXYGENASE 3(NCED3)transcript levels and abscisic acid(ABA)contents in leaves as well as increased hydrogen peroxide(H_(2)O_(2))levels in roots and leaves.Grafting experiments distinctly illustrate that drought resistance can be conferred by the frd3 rootstock regardless of the scion genotype,indicating that long-distance signals originating from frd3 roots promote an increase in ABA levels in leaves.Intriguingly,the drought resistance conferred by the frd3 mutant rootstock is weakened by the CAT2-overexpressing scion,suggesting that H_(2)O_(2)may be involved in long-distance signaling.Moreover,the results of comparative transcriptome and proteome analyses support the drought resistance phenotype of the frd3 mutant.Taken together,our findings substantiate the notion that frd3 root-derived long-distance signals trigger ABA synthesis in leaves and enhance drought resistance,providing new evidence for root-to-shoot long-distance signaling in the drought response of plants.

Corrigendum to“Root-derived long-distance signals trigger ABA synthesis and enhance drought resistance in Arabidopsis”[Journal of Genetics and Genomics(2024)51,749e761]

This corrigendum clarifies to supplement the“Data availability”session.Data availability The raw sequence data reported in this paper have been deposited in the National Genomics Data Center,China National Center for Bioinformation/Beijing Institute of Genomics,Chinese Academy of Sciences(GSA:CRA017487 and iProx:IPX0009175000).

Nitrate-responsive OsMADS27 promotes salt tolerance in rice

Salt stress is a major constraint on plant growth and yield.Nitrogen(N)fertilizers are known to alleviate salt stress.However,the underlying molecular mechanisms remain unclear.Here,we show that nitratedependent salt tolerance is mediated by OsMADS27 in rice.The expression of OsMADS27 is specifically induced by nitrate.The salt-inducible expression of OsMADS27 is also nitrate dependent.OsMADS27 knockout mutants are more sensitive to salt stress than the wild type,whereas OsMADS27 overexpression lines are more tolerant.Transcriptomic analyses revealed that OsMADS27 upregulates the expression of a number of known stress-responsive genes as well as those involved in ion homeostasis and antioxidation.We demonstrate that OsMADS27 directly binds to the promoters of OsHKT1.1 and OsSPL7 to regulate their expression.Notably,OsMADS27-mediated salt tolerance is nitrate dependent and positively correlated with nitrate concentration.Our results reveal the role of nitrate-responsive OsMADS27 and its downstream target genes in salt tolerance,providing a molecular mechanism for the enhancement of salt tolerance by nitrogen fertilizers in rice.OsMADS27 overexpression increased grain yield under salt stress in the presence of sufficient nitrate,suggestingthatOsMADS27 is a promising candidate for the improvementof salt tolerance inrice.

Loss of OsARF18 function confers glufosinate resistance in rice

Dear Editor,Weeds are one of the most common biotic stresses causing severe crop yield decline(Jin et al.,2022).Chemical herbicides are an economical and effective method for weed control and are widely used in modern agriculture(Amna et al.,2019).However,the improper use of herbicides can impede crop growth,ultimately leading to reduced crop yields.Therefore,it is of great significance to develop herbicide-resistant crops to alleviate weed infestations and maintain sustainable crop production.

Arabidopsis MADS-Box Transcription Factor AGL21 Acts as Environmental Surveillance of Seed Germination by Regulating ABI5 Expression

Seed germination is a crucial checkpoint for plant survival under unfavorable environmental conditions. Ab- scisic acid （ABA） signaling plays a vital role in integrating environmental information to regulate seed germination. It has been well known that MCMI/AGAMOUS/DEFICIENS/SRF （MADS）-box transcription factors are key regulators of seed and flower development in Arabidopsis. However, little is known about their functions in seed germination. Here we report that MADS-box transcription factor AGL21 is a negative regulator of seed germination and post-germination growth by controlling the expression of ABA-INSENSITIVE 5 （ABIb＇） in Arabidopsis. The AGL21-overexpressing plants were hypersensitive to ABA, salt, and osmotic stresses during seed germination and early post-germination growth, whereas ag121 mutants were less sensitive. We found that AGL21 positively regulated ABI5 expression in seeds. Consistently, genetic analyses showed that AGL21 is epistatic to ABI5 in controlling seed germination. Chromatin immunoprecipitation assays further demonstrated that AGL21 could directly bind to the ABI5 promoter in plant cells. Moreover, we found that AGL21 responded to multiple environmental stresses and plant hormones during seed germination. Taken together, our results suggest that AGL21 acts as a surveillance integrator that incorporates environmental cues and endogenous hormonal signals into ABA signaling to regulate seed germination and early post-germination growth.