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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Plant Sci.</journal-id>
<journal-title>Frontiers in Plant Science</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Plant Sci.</abbrev-journal-title>
<issn pub-type="epub">1664-462X</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.3389/fpls.2023.1193542</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Plant Science</subject>
<subj-group>
<subject>Editorial</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>Editorial: The role of stress proteins in plants under abiotic stress</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author" corresp="yes">
<name>
<surname>Zhou</surname>
<given-names>Peng</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="author-notes" rid="fn001">
<sup>*</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/419444"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Graether</surname>
<given-names>Steffen P.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/116484"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Hu</surname>
<given-names>Longxing</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/293031"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Zhang</surname>
<given-names>Wanjun</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/317272"/>
</contrib>
</contrib-group>    <aff id="aff1">
<sup>1</sup>
<institution>School of Agriculture and Biology, Shanghai Jiao Tong University</institution>, <addr-line>Shanghai</addr-line>, <country>China</country>
</aff>
<aff id="aff2">
<sup>2</sup>
<institution>Department of Molecular and Cellular Biology, University of Guelph Guelph</institution>, <addr-line>Guelph, ON</addr-line>, <country>Canada</country>
</aff>
<aff id="aff3">
<sup>3</sup>
<institution>Department of Grassland Science, College of Agronomy, Hunan Agricultural University</institution>, <addr-line>Changsha</addr-line>, <country>China</country>
</aff>
<aff id="aff4">
<sup>4</sup>
<institution>College of Grassland Science and Technology, China Agricultural University</institution>, <addr-line>Beijing</addr-line>, <country>China</country>
</aff>
<author-notes>
<fn fn-type="edited-by">
<p>Edited and Reviewed by: Junya Mizoi, The University of Tokyo, Japan</p>
</fn>
<fn fn-type="corresp" id="fn001">
<p>*Correspondence: Peng Zhou, <email xlink:href="mailto:pzhou0063@sjtu.edu.cn">pzhou0063@sjtu.edu.cn</email>
</p>
</fn>
</author-notes>
<pub-date pub-type="epub">
<day>04</day>
<month>05</month>
<year>2023</year>
</pub-date>
<pub-date pub-type="collection">
<year>2023</year>
</pub-date>
<volume>14</volume>
<elocation-id>1193542</elocation-id>
<history>
<date date-type="received">
<day>25</day>
<month>03</month>
<year>2023</year>
</date>
<date date-type="accepted">
<day>17</day>
<month>04</month>
<year>2023</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#xa9; 2023 Zhou, Graether, Hu and Zhang</copyright-statement>
<copyright-year>2023</copyright-year>
<copyright-holder>Zhou, Graether, Hu and Zhang</copyright-holder>
<license xlink:href="http://creativecommons.org/licenses/by/4.0/">
<p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</p>
</license>
</permissions>
<related-article id="RA1" related-article-type="commentary-article" xlink:href="https://www.frontiersin.org/research-topics/35794" ext-link-type="uri">Editorial on the Research Topic <article-title>The role of stress proteins in plants under abiotic stress</article-title>
</related-article>
<kwd-group>
<kwd>stress proteins</kwd>
<kwd>functional analysis</kwd>
<kwd>post-translational modification</kwd>
<kwd>bioinformatics analysis</kwd>
<kwd>the stress-associated protein</kwd>
<kwd>the stress-activated protein kinase</kwd>
<kwd>late embryogenesis abundant protein</kwd>
</kwd-group>
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<fig-count count="0"/>
<table-count count="0"/>
<equation-count count="0"/>
<ref-count count="0"/>
<page-count count="2"/>
<word-count count="867"/>
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<custom-meta-wrap>
<custom-meta>
<meta-name>section-at-acceptance</meta-name>
<meta-value>Plant Abiotic Stress</meta-value>
</custom-meta>
</custom-meta-wrap>
</article-meta>
</front>
<body>
<p>Extreme environmental conditions pose significant challenges to plant survival and productivity. Over time, plants have evolved a myriad of defense mechanisms to mitigate the detrimental effects of adverse conditions. These mechanisms induce the production of a plethora of protective proteins, which play a crucial role in preserving the normal physiological and biochemical processes of plants under stress. In-depth investigation of these stress proteins may uncover significant insights into their potential applications in agricultural production.</p>
<p>Various stress proteins have been identified, such as late embryogenesis abundant proteins (LEA proteins, including dehydrins), reactive oxygen species (ROS) scavenging enzymes, heat shock proteins (HSPs) that serve as molecular chaperones to preserve enzyme activity and protein structure, and enzymes responsible for maintaining plant redox status and eliminating oxygen free radicals. Current research has delved into the significance and mechanisms of these stress proteins, expanding our understanding of both their depth and scope. This knowledge has been extensively applied to the study of numerous plant species, ultimately contributing to the enhancement of agricultural production and improvement of ecological environments in the long term.</p>
<p>This Research Topic has been meticulously organized, featuring three original research articles and one comprehensive review, designed to emphasize recent advancements in the following areas: (1) in-depth functional analysis of stress proteins, (2) regulatory networks of stress proteins, (3) bioinformatics analysis of stress proteins within the context of big data, and the cross-species evolutionary relationships of stress proteins.</p>
<sec id="s1">
<title>In-depth functional analysis of stress proteins</title>
<p>A wide array of stress proteins has been identified in various plant species. However, the precise mechanisms through which some of these proteins function within plant cells remain elusive. One such example is the stress-associated protein (SAP) family. SAP family genes have been isolated from diverse plants, including <italic>Arabidopsis thaliana</italic>, <italic>Populus euphratica</italic>, and <italic>Populus trichocarpa</italic>, yet their mode of action within plant cells has not been reported. What is known is that SAPs represent a novel class of highly conserved zinc-finger proteins across different plant species and are intimately associated with stress tolerance in plants.</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fpls.2022.925744">Park et&#xa0;al.</ext-link> employed RNA interference technology to knock down an SAP gene, designated as <italic>PagSAP11</italic>, in hybrid poplar (<italic>Populus alba &#xd7; Populus tremula</italic> var. <italic>glandulosa</italic>). Their findings revealed that the knockdown of <italic>PagSAP11</italic> augmented poplar tolerance to drought stress and promoted the branching of lateral shoots. Additionally, the branching phenotype was associated with the upregulated expression of several genes that are implicated in axillary bud outgrowth and cell proliferation. This study holds considerable value in further elucidating the mechanisms of SAPs within plant cells.</p>
</sec>
<sec id="s2">
<title>Regulatory networks of stress proteins</title>
<p>At the molecular level, plant response mechanisms to stress are multifaceted. Plants can react to stress by activating transcription factors, which in turn regulate the up or downregulation of specific genes. Alternatively, a single gene can produce various mature functional proteins to adapt to environmental changes. Post-translational modification (PTM) represents a crucial regulatory mechanism that enables plants to respond to stress.</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fpls.2022.967607">Xiao et&#xa0;al.</ext-link> conducted a comprehensive review of recent findings regarding the interplay between histone (de)methylation and osmotic stress. They also underscored the influence of stress on histone methylation profiles and the role of histone methylation in optimizing plant performance under stress conditions. Their work offers valuable insights into how histone modifications regulate plant responses to stress.</p>
</sec>
<sec id="s3">
<title>Bioinformatics analysis of stress proteins</title>
<p>Advancements in computer technology and the availability of various species&#x2019; genome databases have facilitated in-depth investigations of stress protein families. Genome-wide analyses of genes encoding stress proteins in specific species can provide novel insights into the distribution of gene families within genomes and the evolutionary relationships of these gene families, even between different species. In conjunction with RNA-seq data, researchers can identify more potent genes within the same gene family.</p>
<p>The stress-activated protein kinase (SAPK), also known as SnRK2, responds to abiotic stress through abscisic acid (ABA)-dependent or independent signaling pathways. SAPKs are promising candidate genes for enhancing plant stress resistance. <ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fpls.2022.922564">Xing et&#xa0;al.</ext-link> identified 10 <italic>LpSAPKs</italic> in perennial ryegrass (<italic>Lolium perenne</italic> L.), with most <italic>LpSAPKs</italic> demonstrating responsiveness to various abiotic stressors. Employing a yeast ectopic expression system, the authors further investigated the role of <italic>LpSAPK9</italic> in plant drought tolerance.</p>
<p>LEA proteins are highly expressed in plants under diverse abiotic stresses, bolstering plant resistance. The LEA protein family encompasses several subfamilies, including LEA_2, which is distinct from other LEA proteins and plays critical roles in plant stress tolerance. To date, the function of LEA_2 remains inadequately understood. <ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fpls.2022.976160">Zhang et&#xa0;al.</ext-link> identified 155 members of <italic>LEA_2</italic> from the alfalfa (<italic>Medicago sativa</italic> L.) genome. Bioinformatics analysis revealed that <italic>MsLEA_2</italic> genes are distributed across all 32 chromosomes, with 85 genes present in gene clusters, accounting for 54.83%. Cis-element analysis confirmed that the promoter region of <italic>MsLEA_2</italic> is rich in ABRE, MBS, LTR, and MeJARE. Additionally, in combination with RNA-seq data, the authors found that <italic>MsLEA_2</italic> genes exhibit stress resistance potential under abiotic stress. These findings hold promise for future functional analyses of LEA_2 proteins.</p>
</sec>
<sec id="s4" sec-type="author-contributions">
<title>Author contributions</title>
<p>PZ wrote the paper. SG, LH, and WZ had revised it. All authors contributed to the article and approved the submitted version.</p>
</sec>
</body>
<back>
<ack>
<title>Acknowledgments</title>
<p>We express our sincere gratitude to all the authors who contributed their original research articles or reviews to this Research Topic. We also extend our appreciation to all the reviewers for their diligent efforts and timely responses.</p>
</ack>
<sec id="s5" sec-type="COI-statement">
<title>Conflict of interest</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
<sec id="s6" sec-type="disclaimer">
<title>Publisher&#x2019;s note</title>
<p>All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.</p>
</sec>
</back>
</article>