{"title":"<i>Heading Date 3a</i> Stimulates Tiller Bud Outgrowth in <i>Oryza sativa</i> L. through Strigolactone Signaling Pathway.","authors":"Qiqi Zheng, Zejiao Zhou, Xinran Li, Yingshan Lan, Ruihua Huang, Shengchun Zhang, Hongqing Li","doi":"10.3390/ijms251910778","DOIUrl":null,"url":null,"abstract":"<p><p><i>Heading date 3a (Hd3a</i>, a <i>FLOWERING LOCUS T</i> (<i>FT</i>) ortholog from rice) is well known for its important role in rice (<i>Oryza sativa</i> L.), controlling floral transition under short-day (SD) conditions. Although the effect of <i>Hd3a</i> on promoting branching has been found, the underlying mechanism remains largely unknown. In this report, we overexpressed an <i>Hd3a</i> and <i>BirAG</i> (encoding a biotin ligase) fusion gene in rice, and found that early flowering and tiller bud outgrowth was promoted in <i>BHd3aOE</i> transgenic plants. On the contrary, knockout of <i>Hd3a</i> delayed flowering and tiller bud outgrowth. By using the BioID method, we identified multiple Hd3a proximal proteins. Among them, D14, D53, TPR1, TPR2, and TPRs are central components of the strigolactone signaling pathway, which has an inhibitory effect on rice tillering. The interaction between Hd3a, on the one hand, and D14 and D53 was further confirmed by the bimolecular fluorescence complementation (BiFC), yeast two-hybrid (Y2H), and co-immunoprecipitation (Co-IP) methods. We also found that Hd3a prevented the degradation of D53 induced by rac-GR24 (a strigolactone analog) in rice protoplasts. RT-qPCR assay showed that the expression levels of genes involved in strigolactone biosynthesis and signal transduction were altered significantly between WT and <i>Hd3a</i> overexpression (<i>Hd3aOE</i>) or mutant (<i>hd3a</i>) plants. <i>OsFC1</i>, a downstream target of the strigolactone signaling transduction pathway in controlling rice tillering, was downregulated significantly in <i>Hd3aOE</i> plants, whereas it was upregulated in <i>hd3a</i> lines. Collectively, these results indicate that <i>Hd3a</i> promotes tiller bud outgrowth in rice by attenuating the negative effect of strigolactone signaling on tillering and highlight a novel molecular network regulating rice tiller outgrowth by <i>Hd3a</i>.</p>","PeriodicalId":14156,"journal":{"name":"International Journal of Molecular Sciences","volume":null,"pages":null},"PeriodicalIF":5.6000,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11476357/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Molecular Sciences","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.3390/ijms251910778","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Heading date 3a (Hd3a, a FLOWERING LOCUS T (FT) ortholog from rice) is well known for its important role in rice (Oryza sativa L.), controlling floral transition under short-day (SD) conditions. Although the effect of Hd3a on promoting branching has been found, the underlying mechanism remains largely unknown. In this report, we overexpressed an Hd3a and BirAG (encoding a biotin ligase) fusion gene in rice, and found that early flowering and tiller bud outgrowth was promoted in BHd3aOE transgenic plants. On the contrary, knockout of Hd3a delayed flowering and tiller bud outgrowth. By using the BioID method, we identified multiple Hd3a proximal proteins. Among them, D14, D53, TPR1, TPR2, and TPRs are central components of the strigolactone signaling pathway, which has an inhibitory effect on rice tillering. The interaction between Hd3a, on the one hand, and D14 and D53 was further confirmed by the bimolecular fluorescence complementation (BiFC), yeast two-hybrid (Y2H), and co-immunoprecipitation (Co-IP) methods. We also found that Hd3a prevented the degradation of D53 induced by rac-GR24 (a strigolactone analog) in rice protoplasts. RT-qPCR assay showed that the expression levels of genes involved in strigolactone biosynthesis and signal transduction were altered significantly between WT and Hd3a overexpression (Hd3aOE) or mutant (hd3a) plants. OsFC1, a downstream target of the strigolactone signaling transduction pathway in controlling rice tillering, was downregulated significantly in Hd3aOE plants, whereas it was upregulated in hd3a lines. Collectively, these results indicate that Hd3a promotes tiller bud outgrowth in rice by attenuating the negative effect of strigolactone signaling on tillering and highlight a novel molecular network regulating rice tiller outgrowth by Hd3a.
期刊介绍:
The International Journal of Molecular Sciences (ISSN 1422-0067) provides an advanced forum for chemistry, molecular physics (chemical physics and physical chemistry) and molecular biology. It publishes research articles, reviews, communications and short notes. Our aim is to encourage scientists to publish their theoretical and experimental results in as much detail as possible. Therefore, there is no restriction on the length of the papers or the number of electronics supplementary files. For articles with computational results, the full experimental details must be provided so that the results can be reproduced. Electronic files regarding the full details of the calculation and experimental procedure, if unable to be published in a normal way, can be deposited as supplementary material (including animated pictures, videos, interactive Excel sheets, software executables and others).