{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T08:35:05Z","timestamp":1775032505098,"version":"3.50.1"},"reference-count":49,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T00:00:00Z","timestamp":1775001600000},"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                    Grain size is a critical determinant of rice yield. Despite the identification of several genes involved in grain size regulation, the underlying molecular mechanisms remain incompletely understood. A comprehensive understanding of the genetic and molecular mechanisms that regulate seed size is crucial for improving crop yield. Here, we report the characterization of\n                    <jats:italic>SMALL GRAIN 5<\/jats:italic>\n                    (\n                    <jats:italic>SMG5<\/jats:italic>\n                    ), which encodes a heat shock transcription factor (HSF) and serves as a key regulator of both grain size and plant architecture in rice. The\n                    <jats:italic>smg5<\/jats:italic>\n                    mutant exhibits pleiotropic phenotypes, including significantly reduced grain size, as well as decreased plant height, leaf width, tiller number, and grain number per panicle.\n                    <jats:italic>SMG5<\/jats:italic>\n                    regulates grain size through both cell expansion and cell proliferation. It is expressed in developing panicles, and the GFP-SMG5 fusion protein is localized in the nucleus. Integrated RNA-seq and DAP-seq analyses reveal that SMG5 binds to the promoter region of\n                    <jats:italic>DGS1<\/jats:italic>\n                    and directly modulates its expression. Notably, overexpression of\n                    <jats:italic>SMG5<\/jats:italic>\n                    resulted in larger grains. These findings establish SMG5 as a key HSF that modulates grain size and plant architecture, providing insights into the regulatory network controlling grain development in rice.\n                  <\/jats:p>","DOI":"10.3389\/fpls.2026.1783348","type":"journal-article","created":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T05:42:06Z","timestamp":1775022126000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["SMALL GRAIN 5 encodes a heat shock transcription factor controlling grain size and plant architecture in rice"],"prefix":"10.3389","volume":"17","author":[{"given":"Chenjie","family":"Wang","sequence":"first","affiliation":[{"name":"School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University","place":["Sanya, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nannan","family":"Han","sequence":"additional","affiliation":[{"name":"School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University","place":["Sanya, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhao","family":"Li","sequence":"additional","affiliation":[{"name":"School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University","place":["Sanya, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chen","family":"Zhou","sequence":"additional","affiliation":[{"name":"School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University","place":["Sanya, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guansong","family":"Li","sequence":"additional","affiliation":[{"name":"School of Breeding and Multiplication (Sanya Institute of Breeding and Multiplication), Hainan University","place":["Sanya, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yongqing","family":"Pan","sequence":"additional","affiliation":[{"name":"Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences","place":["Beijing, China"]},{"name":"University of Chinese Academy of Sciences","place":["Beijing, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Baolan","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences","place":["Beijing, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ke","family":"Huang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University","place":["Kaifeng, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yunhai","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences","place":["Beijing, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yingjie","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Seed Innovation, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences","place":["Beijing, China"]},{"name":"Hainan Seed Industry Laboratory","place":["Sanya, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,1]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"174","DOI":"10.1038\/nbt.2095","article-title":"Genome sequencing reveals agronomically important loci in rice using MutMap","volume":"30","author":"Abe","year":"2012","journal-title":"Nat. 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