Biology subjects

Alfatih, A.

Publications and source records attributed to Alfatih, A..

5 recordsLinked to original sources

bioRxiv2022

Nitrate-dependent salt tolerance mediated by OsNLP4-OsMADS27 module

Salt stress is a major constraint of plant growth and yield. Nitrogen (N) fertilizers are known to alleviate salt stress. However, the underlying molecular mechanisms remain unclear. Here we show that OsNLP4-OsMADS27 module controls nitrate-dependent salt tolerance in rice. The expression of OsMADS27 is specifically induced by nitrate. The OsMADS27 knockout mutants are more sensitive to salt stress than the wild type, whereas the OsMADS27 overexpression lines are more tolerant. Transcriptomic analyses revealed that OsMADS27 controls the expression of a number of known stress-responsive genes as well as those involved in ion homeostasis and antioxidation. We demonstrated that OsMADS27 directly binds to the promoter of OsHKT1.1 and OsSPL7 to regulate their expression. Notably, OsMADS27-mediated salt tolerance is nitrate-dependent and positively correlated with nitrate concentration. We further showed that OsNLP4, a nitrate-responsive key regulator in N metabolism and N use efficiency, positively regulates the expression of OsMADS27 by directly binding to the nitrate-responsive cis-element in its promoter, thereby transmitting the nitrate signal to OsMADS27 and conferring its nitrate dependence. Our results reveal the role of nitrate-responsive OsNLP4-OsMADS27 module and its downstream target genes in salt tolerance, filling the gap in the molecular mechanism of nitrate-dependent salt tolerance of rice. Moreover, OsMADS27 overexpression increased grain yield under salt stress in presence of sufficient nitrate, indicating that OsMADS27 is a promising candidate for the improvement of salt tolerance in rice.

plant biology↗

bioRxiv2021

Rice NIN-LIKE PROTEIN 3 plays a significant role in nitrogen use efficiency and grain yield under nitrate-sufficient conditions

Nitrogen (N) is an essential macronutrient for crop growth and yield, but excessive application of N fertilizer has caused serious environmental pollution and greatly increased the cost of agricultural production. One of the effective and economical solutions to this dilemma is to improve the N use efficiency (NUE) of crops. Although some components involved in regulating NUE have been identified, the underlying molecular mechanism remains largely elusive in rice. Here we report that the OsNLP3 (NIN-like protein 3) is an important regulator in NUE and grain yield under nitrate-sufficient conditions. Both NUE and grain yield were significantly improved by enhanced OsNLP3 expression in the field, but reduced in osnlp3 mutants. The expression of OsNLP3 responds to both nitrate and ammonium, while OsNLP3 nuclear retention is only induced by nitrate, not by ammonium. OsNLP3 regulates the expression of a set of genes involved in N transport and assimilation by directly binding to the nitrate-responsive cis-element in the promoters of these genes. Our study demonstrates that OsNLP3 is significant for the regulation of NUE and grain yield, particularly in nitrate-rich conditions, thus providing a candidate for improving NUE and grain yield in rice.

plant biology↗

bioRxiv2020

Loss of rice PARAQUAT TOLERANCE 3 confers enhanced resistance to abiotic stresses and increases grain yield in field

Plants frequently suffer from environmental stresses in nature and have evolved sophisticated and efficient mechanisms to cope with the stresses. To balance between growth and stress response, plants are equipped with efficient means to switch off the activated stress responses when stresses diminish. We previously revealed such an off-switch mechanism conferred by Arabidopsis PQT3, knockout of which significantly enhances resistance to abiotic stresses. To explore whether the rice homolog OsPQT3 is functionally conserved, we generated three knockout mutants with CRISPR-Cas9 technology. The OsPQT3 knockout mutants (ospqt3) display enhanced resistance to oxidative and salt stress with elevated expression of OsGPX1, OsAPX1, and OsSOD1. More importantly, the ospqt3 mutants show significantly enhanced agronomic performance with higher yield compared with the wild type under salt stress in greenhouse as well as in field conditions. We further showed that OsPQT3 was rapidly down regulated in response to oxidative and other abiotic stresses as AtPQT3. Taken together, these results support our previous findings that AtPQT3 acts as an off-switch in stress response, which is well conserved in rice. Therefore, PQT3 locus provides a promising candidate for crop improvement with enhanced stress resistance by gene editing technology.

plant biology↗

bioRxiv2020

Rice NIN-LIKE PROTEIN 1 Rapidly Responds to Nitrogen Deficiency and Improves Yield and Nitrogen Use Efficiency

Nitrogen (N) is indispensable for crop growth and yield, but excessive agricultural application of nitrogenous fertilizers has generated severe environmental problems. A desirable and economical solution to cope with these issues is to improve crop nitrogen use efficiency (NUE). Plant NUE has been a focal point of intensive research worldwide, yet much more has to be learned about its genetic determinants and regulation. Here, we show that rice NIN-LIKE PROTEIN 1 (OsNLP1) plays a fundamental role in N utilization. OsNLP1 protein localizes in nucleus and its transcript level is rapidly induced by N starvation. Overexpression of OsNLP1 improves plant growth, grain yield and NUE under different N conditions while knockout of OsNLP1 impairs grain yield and NUE under N limiting conditions. OsNLP1 regulates nitrate and ammonium utilization by cooperatively orchestrating multiple N uptake and assimilation genes. Chromatin immunoprecipitation and yeast-one-hybrid assays show that OsNLP1 can directly bind to the promoter of these genes to activate their expression. Therefore, our results demonstrate that OsNLP1 is a key regulator of N utilization and represents a potential target for improving NUE and yield in rice. One-sentence summaryOsNLP1 rapidly responds to N availability, enhances N uptake and assimilation, and holds great potential in promoting high yield in rice.

plant biology↗

bioRxiv2020

Rice NIN-LIKE PROTEIN 4 is a master regulator of nitrogen use efficiency

Nitrogen (N) is one of the key essential macronutrients that affects rice growth and yield. Inorganic N fertilizers are excessively used to boost yield and generate serious collateral environmental pollution. Therefore, improving crop N use efficiency (NUE) is highly desirable and has been a major endeavor in crop improvement. However, only a few regulators have been identified that can be used to improve NUE in rice to date. Here we show that the NIN-like protein OsNLP4 significantly improves the rice NUE and yield. Field trials consistently showed that loss-of-OsNLP4 dramatically reduced yield and NUE compared with wild type under different N regimes. In contrast, the OsNLP4 overexpression lines remarkably increased yield by 30% and NUE by 47% under moderate N level compared with wild type. Transcriptomic analyses revealed that OsNLP4 orchestrates the expression of a majority of known N uptake, assimilation and signaling genes by directly binding to the nitrate-responsive cis-element in their promoters to regulate their expression. Moreover, overexpression of OsNLP4 can recover the phenotype of Arabidopsis nlp7 mutant and enhance its biomass. Our results demonstrate that OsNLP4 is a master regulator of NUE in rice and sheds light on crop NUE improvement.

plant biology↗