{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T05:04:05Z","timestamp":1784783045090,"version":"3.55.0"},"reference-count":45,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T00:00:00Z","timestamp":1784764800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Plant Sci."],"abstract":"<jats:p>\n                    The mesophyll protoplast transient expression system is an essential and robust methodology for examining gene expression regulation. Despite its potential, it has not been effectively employed to elucidate the genetic regulatory pathways and networks underlying plant responses to nutrient starvation, such as those involving phosphorus (Pi) and iron (Fe). In this study, we identified differentially expressed genes in response to Pi starvation in\n                    <jats:italic>Arabidopsis<\/jats:italic>\n                    using transcriptome analysis and RT-qPCR validation. Our findings revealed that Pi starvation significantly upregulated the expression of Pi-starvation induced (\n                    <jats:italic>PSI<\/jats:italic>\n                    ) genes, including\n                    <jats:italic>SPX1<\/jats:italic>\n                    ,\n                    <jats:italic>SPX3<\/jats:italic>\n                    ,\n                    <jats:italic>IPS1<\/jats:italic>\n                    , and\n                    <jats:italic>PS2<\/jats:italic>\n                    , while simultaneously downregulating the expression of Fe starvation-responsive genes, such as\n                    <jats:italic>FIT<\/jats:italic>\n                    ,\n                    <jats:italic>IRT1<\/jats:italic>\n                    , and\n                    <jats:italic>FRO2<\/jats:italic>\n                    . Additionally, through a dual luciferase transient expression assay in mesophyll protoplasts, we demonstrated that the transcription factor PHR1 serves as a crucial transcriptional regulator, modulating the expression of phosphate starvation response (\n                    <jats:italic>PSR<\/jats:italic>\n                    ) genes. This regulation significantly enhances the transcriptional activity of the\n                    <jats:italic>SPX1<\/jats:italic>\n                    ,\n                    <jats:italic>SPX2<\/jats:italic>\n                    ,\n                    <jats:italic>SPX3<\/jats:italic>\n                    ,\n                    <jats:italic>IPS1<\/jats:italic>\n                    ,\n                    <jats:italic>PS2<\/jats:italic>\n                    , and\n                    <jats:italic>PHT1;4<\/jats:italic>\n                    promoters. Upon the addition of the SPX1 protein, the activation of these gene promoters by PHR1 were alleviated. Concurrently, the transcriptional regulator FIT, which governs the expression of genes responsive to Fe starvation, markedly increased the transcriptional activity of the\n                    <jats:italic>IRT1<\/jats:italic>\n                    and\n                    <jats:italic>FRO2<\/jats:italic>\n                    promoters. Based on these findings, we propose the mesophyll protoplast transient expression system as a rapid and reliable method for investigating complex genetic networks. Overall, our study provides substantial evidence for understanding the role of the mesophyll protoplast transient expression system in elucidating the genetic regulatory pathways and networks involved in plant responses to nutrient starvation.\n                  <\/jats:p>","DOI":"10.3389\/fpls.2026.1825102","type":"journal-article","created":{"date-parts":[[2026,7,23]],"date-time":"2026-07-23T04:31:44Z","timestamp":1784781104000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Mesophyll protoplasts: a key tool for deciphering plant nutrient starvation pathways"],"prefix":"10.3389","volume":"17","author":[{"given":"Tian","family":"Yashan","sequence":"first","affiliation":[{"name":"Shaanxi Key Laboratory of Research and Utilization of Resource Plants on the Loess Plateau, College of Life Sciences, Yan\u2019an University","place":["Yan\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"She","family":"Jianju","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Research and Utilization of Resource Plants on the Loess Plateau, College of Life Sciences, Yan\u2019an University","place":["Yan\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lin","family":"Jinhui","sequence":"additional","affiliation":[{"name":"Fruit Research Institute, Fujian Academy of Agricultural Sciences","place":["Fuzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chen","family":"Feng","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Research and Utilization of Resource Plants on the Loess Plateau, College of Life Sciences, Yan\u2019an University","place":["Yan\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Song","family":"Zhuoran","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Research and Utilization of Resource Plants on the Loess Plateau, College of Life Sciences, Yan\u2019an University","place":["Yan\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liu","family":"Jiayi","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Research and Utilization of Resource Plants on the Loess Plateau, College of Life Sciences, Yan\u2019an University","place":["Yan\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"He","family":"Yan","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Research and Utilization of Resource Plants on the Loess Plateau, College of Life Sciences, Yan\u2019an University","place":["Yan\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ma","family":"Junhan","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Research and Utilization of Resource Plants on the Loess Plateau, College of Life Sciences, Yan\u2019an University","place":["Yan\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cheng","family":"Guoting","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Research and Utilization of Resource Plants on the Loess Plateau, College of Life Sciences, Yan\u2019an University","place":["Yan\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wang","family":"Yanfeng","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Research and Utilization of Resource Plants on the Loess Plateau, College of Life Sciences, Yan\u2019an University","place":["Yan\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dang","family":"Fengfeng","sequence":"additional","affiliation":[{"name":"Shaanxi Key Laboratory of Research and Utilization of Resource Plants on the Loess Plateau, College of Life Sciences, Yan\u2019an University","place":["Yan\u2019an, Shaanxi, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,7,23]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"168","DOI":"10.1016\/j.pbi.2017.04.016","article-title":"Phosphate scouting by root tips","volume":"39","author":"Abel","year":"2017","journal-title":"Curr. 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