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GAF domain is essential for nitrate-dependent AtNLP7 function.

ABSTRACT: Nitrate is an essential nutrient and an important signaling molecule in plants. However, the molecular mechanisms by which plants perceive nitrate deficiency signaling are still not well understood. Here we report that AtNLP7 protein transport from the nucleus to the cytoplasm in response to nitrate deficiency is dependent on the N-terminal GAF domain. With the deletion of the GAF domain, AtNLP7^ΔGAF always remains in the nucleus regardless of nitrate availability. AtNLP7 ^ΔGAF also shows reduced activation of nitrate-induced genes due to its impaired binding to the nitrate-responsive cis-element (NRE) as well as decreased growth like nlp7-1 mutant. In addition, AtNLP7^ΔGAF is unable to mediate the reduction of reactive oxygen species (ROS) accumulation upon nitrate treatment. Our investigation shows that the GAF domain of AtNLP7 plays a critical role in the sensing of nitrate deficiency signal and in the nitrate-triggered ROS signaling process.

SUBMITTER: Wu J

PROVIDER: S-EPMC9310391 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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GAF domain is essential for nitrate-dependent AtNLP7 function.

Wu Jie J Song Ying Y Zhang Zi-Sheng ZS Wang Jing-Xian JX Zhang Xuan X Zang Jian-Ye JY Bai Ming-Yi MY Yu Lin-Hui LH Xiang Cheng-Bin CB

BMC plant biology 20220725 1

Nitrate is an essential nutrient and an important signaling molecule in plants. However, the molecular mechanisms by which plants perceive nitrate deficiency signaling are still not well understood. Here we report that AtNLP7 protein transport from the nucleus to the cytoplasm in response to nitrate deficiency is dependent on the N-terminal GAF domain. With the deletion of the GAF domain, AtNLP7<sup>ΔGAF</sup> always remains in the nucleus regardless of nitrate availability. AtNLP7 <sup>ΔGAF</su ...[more]

PMID: 35871642

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