S-Nitrosylation Positively Regulates Ascorbate Peroxidase Activity during Plant Stress Responses

Inter-organ communication and the heat stress (HS; 45°C, 6 h) responses of organs exposed and not directly exposed to HS were evaluated in rice (Oryza sativa) by comparing the impact of HS applied either to whole plants, or only to shoots or roots. Whole-plant HS reduced photosynthetic activity (Fv/Fm and QY_Lss), but this effect was alleviated by prior acclimation (37°C, 2 h). Dynamics of HSFA2d, HSP90.2, HSP90.3, and SIG5 expression revealed high protection of crowns and roots. Additionally, HSP26.2 was strongly expressed in leaves. Whole-plant HS increased levels of jasmonic acid (JA) and cytokinin cis-zeatin in leaves, while up-regulating auxin indole-3-acetic acid and down-regulating trans-zeatin in leaves and crowns. Ascorbate peroxidase activity and expression of alternative oxidases (AOX) increased in leaves and crowns. HS targeted to leaves elevated levels of JA in roots, cis-zeatin in crowns, and ascorbate peroxidase activity in crowns and roots. HS targeted to roots increased levels of abscisic acid and auxin in leaves and crowns, cis-zeatin in leaves, and JA in crowns, while reducing trans-zeatin levels. The weaker protection of leaves reflects the growth strategy of rice. HS treatment of individual organs induced changes in phytohormone levels and antioxidant enzyme activity in non-exposed organs, in order to enhance plant stress tolerance.

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Faculty Opinions recommendation of Mapping proteome-wide targets of protein kinases in plant stress responses.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.737278120.793570463 ◽

2020 ◽

Author(s):

Shuhua Yang

Keyword(s):

Protein Kinases ◽

Stress Responses ◽

Plant Stress ◽

Plant Stress Responses

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Versatile Physiological Functions of Plant GSK3-Like Kinases

Genes ◽

10.3390/genes12050697 ◽

2021 ◽

Vol 12 (5) ◽

pp. 697

Author(s):

Juan Mao ◽

Wenxin Li ◽

Jing Liu ◽

Jianming Li

Keyword(s):

Stress Responses ◽

Glycogen Synthase ◽

Plant Stress ◽

Normal Growth ◽

Growth Conditions ◽

Genetic Studies ◽

Physiological Functions ◽

Environmental Signals ◽

Plant Stress Responses ◽

Diverse Plant

The plant glycogen synthase kinase 3 (GSK3)-like kinases are highly conserved protein serine/threonine kinases that are grouped into four subfamilies. Similar to their mammalian homologs, these kinases are constitutively active under normal growth conditions but become inactivated in response to diverse developmental and environmental signals. Since their initial discoveries in the early 1990s, many biochemical and genetic studies were performed to investigate their physiological functions in various plant species. These studies have demonstrated that the plant GSK3-like kinases are multifunctional kinases involved not only in a wide variety of plant growth and developmental processes but also in diverse plant stress responses. Here we summarize our current understanding of the versatile physiological functions of the plant GSK3-like kinases along with their confirmed and potential substrates.

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OsNAC45 is Involved in ABA Response and Salt Tolerance in Rice

Rice ◽

10.1186/s12284-020-00440-1 ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Xiang Zhang ◽

Yan Long ◽

Jingjing Huang ◽

Jixing Xia

Keyword(s):

Transcription Factors ◽

Salt Stress ◽

Salt Tolerance ◽

Stress Responses ◽

Crop Yields ◽

Plant Stress ◽

Root Cells ◽

Nac Transcription Factors ◽

Rice Plants ◽

Plant Stress Responses

Abstract Background Salt stress threatens crop yields all over the world. Many NAC transcription factors have been reported to be involved in different abiotic stress responses, but it remains unclear how loss of these transcription factors alters the transcriptomes of plants. Previous reports have demonstrated that overexpression of OsNAC45 enhances salt and drought tolerance in rice, and that OsNAC45 may regulate the expression of two specific genes, OsPM1 and OsLEA3–1. Results Here, we found that ABA repressed, and NaCl promoted, the expression of OsNAC45 in roots. Immunostaining showed that OsNAC45 was localized in all root cells and was mainly expressed in the stele. Loss of OsNAC45 decreased the sensitivity of rice plants to ABA and over-expressing this gene had the opposite effect, which demonstrated that OsNAC45 played an important role during ABA signal responses. Knockout of OsNAC45 also resulted in more ROS accumulation in roots and increased sensitivity of rice to salt stress. Transcriptome sequencing assay found that thousands of genes were differently expressed in OsNAC45-knockout plants. Most of the down-regulated genes participated in plant stress responses. Quantitative real time RT-PCR suggested that seven genes may be regulated by OsNAC45 including OsCYP89G1, OsDREB1F, OsEREBP2, OsERF104, OsPM1, OsSAMDC2, and OsSIK1. Conclusions These results indicate that OsNAC45 plays vital roles in ABA signal responses and salt tolerance in rice. Further characterization of this gene may help us understand ABA signal pathway and breed rice plants that are more tolerant to salt stress.

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