Excessive accumulation of chloride(Cl^(-))in the aboveground tissues under saline conditions is harmful to crops.Increasing the exclusion of Cl^(-) from shoots promotes salt tolerance in various crops.However,the unde...Excessive accumulation of chloride(Cl^(-))in the aboveground tissues under saline conditions is harmful to crops.Increasing the exclusion of Cl^(-) from shoots promotes salt tolerance in various crops.However,the underlying molecular mechanisms remain largely unknown.In this study,we demonstrated that a type A response regulator(ZmRR1)modulates Cl^(-) exclusion from shoots and underlies natural variation of salt tolerance in maize.ZmRR1 negatively regulates cytokinin signaling and salt tolerance,likely by interacting with and inhibiting His phosphotransfer(HP)proteins that are key mediators of cytokinin signaling.A naturally occurring non-synonymous SNP variant enhances the interaction between ZmRR1 and ZmHP2,conferring maize plants with a salt-hypersensitive phenotype.We found that ZmRR1 undergoes degradation under saline conditions,leading to the release of ZmHP2 from ZmRR1 inhibition,and subsequently ZmHP2-mediated signaling improves salt tolerance primarily by promoting Cl^(-) exclusion from shoots.Furthermore,we showed that ZmMATE29 is transcriptionally upregulated by ZmHP2-mediated signaling under highly saline conditions and encodes a tonoplast-located Cl^(-) transporter that promotes Cl^(-) exclusion from shoots by compartmentalizing Cl^(-) into the vacuoles of root cortex cells.Collectively,our study provides an important mechanistic understanding of the cytokinin signaling-mediated promotion of Cl^(-) exclusion from shoots and salt tolerance and suggests that genetic modification to promote Cl^(-) exclusion from shoots is a promising route for developing salt-tolerant maize.展开更多
We investigated the effects of salt stress on proline accumulation in the seedling of Elymus dahuricus Turcz. from two different geographic regions in order to explicit various adaptability in response to salt stress ...We investigated the effects of salt stress on proline accumulation in the seedling of Elymus dahuricus Turcz. from two different geographic regions in order to explicit various adaptability in response to salt stress condition. Plants were dealt with in five salt treatments(0%, 0.5%, 1%, 2%, 3%). Significant differences were obvious at the highest salinity treatments for almost each considered parameters. Given that proline concentration is closely related to salt tolerance, we found that G2 seemed to be more tolerant. Furthermore, the proline concentration might be exploited as a dependable measure for evaluating the effect of considering regional factors on salt tolerance.展开更多
基金the financial support from National Key Research and Development Program of China(2022YFA1300061 to C.J.,2022YFD1900704 and 2021YFF1000500 to J.Z.)Beijing Outstanding Young Scientist Program(BJJWZYJH01201910019026 to F.Q.)+2 种基金National Natural Science Foundation of China(32070306 to J.Z.)the Chinese Universities Scientific Fund(15051011 to C.J.,2022RC046 to J.Z.)the 2115 Talent Development Program of China Agricultural University.
文摘Excessive accumulation of chloride(Cl^(-))in the aboveground tissues under saline conditions is harmful to crops.Increasing the exclusion of Cl^(-) from shoots promotes salt tolerance in various crops.However,the underlying molecular mechanisms remain largely unknown.In this study,we demonstrated that a type A response regulator(ZmRR1)modulates Cl^(-) exclusion from shoots and underlies natural variation of salt tolerance in maize.ZmRR1 negatively regulates cytokinin signaling and salt tolerance,likely by interacting with and inhibiting His phosphotransfer(HP)proteins that are key mediators of cytokinin signaling.A naturally occurring non-synonymous SNP variant enhances the interaction between ZmRR1 and ZmHP2,conferring maize plants with a salt-hypersensitive phenotype.We found that ZmRR1 undergoes degradation under saline conditions,leading to the release of ZmHP2 from ZmRR1 inhibition,and subsequently ZmHP2-mediated signaling improves salt tolerance primarily by promoting Cl^(-) exclusion from shoots.Furthermore,we showed that ZmMATE29 is transcriptionally upregulated by ZmHP2-mediated signaling under highly saline conditions and encodes a tonoplast-located Cl^(-) transporter that promotes Cl^(-) exclusion from shoots by compartmentalizing Cl^(-) into the vacuoles of root cortex cells.Collectively,our study provides an important mechanistic understanding of the cytokinin signaling-mediated promotion of Cl^(-) exclusion from shoots and salt tolerance and suggests that genetic modification to promote Cl^(-) exclusion from shoots is a promising route for developing salt-tolerant maize.
文摘We investigated the effects of salt stress on proline accumulation in the seedling of Elymus dahuricus Turcz. from two different geographic regions in order to explicit various adaptability in response to salt stress condition. Plants were dealt with in five salt treatments(0%, 0.5%, 1%, 2%, 3%). Significant differences were obvious at the highest salinity treatments for almost each considered parameters. Given that proline concentration is closely related to salt tolerance, we found that G2 seemed to be more tolerant. Furthermore, the proline concentration might be exploited as a dependable measure for evaluating the effect of considering regional factors on salt tolerance.
