Biology subjects

Sun, L.-Q.

Publications and source records attributed to Sun, L.-Q..

3 recordsLinked to original sources

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↗

bioRxiv2021

AGL16 negatively modulates stress response to balance with growth

Sensile plants constantly experience environmental stresses in nature. They must have evolved effective mechanisms to balance growth with stress response. Here we report the MADS-box transcription factor AGL16 acting as a negative regulator in stress response. Loss-of-AGL16 confers resistance to salt stress in seed germination, root elongation, and soil-grown plants, while elevated AGL16 expression confers the opposite phenotypes compared with wild type. However, the sensitivity to ABA in seed germination is inversely correlated with AGL16 expression level. Transcriptomic comparison revealed that the improved salt resistance of agl16 mutant was largely attributed to enhanced expression of stress responsive transcriptional factors and genes involved in ABA signaling and ion homeostasis. We further demonstrated that AGL16 directly binds to the CArG motifs in the promoter of HKT1;1, HsfA6a, and MYB102 and represses their expression. Genetic analyses with double mutants also support that HsfA6a and MYB102 are target genes of AGL16. Taken together, our results show that AGL16 acts as negative regulator transcriptionally suppressing key components in stress response and may play a critical role in balancing stress response with growth.

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↗