The Plant Journal最新文献

{"title":"Genomic insights into trichome and inflorescence evolution of the palaeopolyploid tree genus Greyia.","authors":"Xiao Ma, Jiyang Chang, Jana Botes, Yves Van de Peer, Dave Kenneth Berger","doi":"10.1111/tpj.71134","DOIUrl":"https://doi.org/10.1111/tpj.71134","url":null,"abstract":"<p><p>The southern African endemic tree Greyia Hook. & Harv. (Francoaceae, Geraniales) comprises three species distinguished by striking variation in trichome morphology and inflorescence architecture, yet the genomic and regulatory basis of these traits has remained largely unexplored. Here, we present chromosome-scale genome assemblies for all recognised Greyia species, namely Greyia radlkoferi, Greyia sutherlandii, and Greyia flanaganii, providing the first high-quality genomic resources for Geraniales. Phylogenomic analyses placed Geraniales as sister to Crossosomatales, with divergence at ~103 million years ago (Mya), and indicated that Greyia diversified recently during the Quaternary (~1.39 Mya). Comparative genomics revealed a Greyia-specific palaeo-hexaploidisation event dated to ~87 Mya, followed by fractionation but with extensive retention of ancestral gene sets in either triplicated or duplicated states across syntenic regions. Transcriptomic analyses revealed regulatory divergence in the conserved MYB-bHLH-WD40 (MBW) network likely associated with variation in trichome morphology, including undetectable GL1 expression and altered GL3/EGL3 expression in G. sutherlandii. In addition, analyses of flower and inflorescence traits identified expansion of MADS-box transcription factor families and species-specific cis-regulatory divergence in LFY and FT. Notably, predicted AGL6 binding sites are retained in the LFY and FT promoters of G. radlkoferi and G. sutherlandii but absent in G. flanaganii, consistent with differences in inflorescence density among species. Together, these results demonstrate how polyploidy and regulatory divergence of conserved developmental pathways have shaped morphological diversification in Greyia.</p>","PeriodicalId":233,"journal":{"name":"The Plant Journal","volume":"128 1","pages":"e71134"},"PeriodicalIF":6.2,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149222846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of methylation and structural variants in shaping the recombination landscape of barley.","authors":"Federico Casale, Christopher Arlt, Marius Kühl, Jinquan Li, Julia Engelhorn, Thomas Hartwig, Benjamin Stich","doi":"10.1111/tpj.71171","DOIUrl":"10.1111/tpj.71171","url":null,"abstract":"<p><p>Meiotic recombination is not only a key mechanism for sexual adaptation in eukaryotes but crucial for the accumulation of beneficial alleles in breeding populations. The effective manipulation of recombination requires, however, a better understanding of the mechanisms regulating the rate and distribution of recombination events in genomes. Here, we identified the genomic features that best explain the recombination variation among a diverse set of segregating populations of barley at a resolution of 1 Mbp and investigated how methylation and structural variants (SVs) determine crossover (CO) hotspots and coldspots at a high resolution of 10 kb. Hotspots were found to be in proximity to genes, and the genetic effects not assigned to methylation were found to be the most important factor explaining differences in recombination rates among populations, along with the methylation and the parental sequence divergence. Interestingly, coldspots were associated with the inheritance of a highly methylated genomic fragment from one parent only, but hotspots were identified at genomic segments where both parents were equally low methylated. The parental sequence divergence was shown to have a sigmoidal correlation with recombination, indicating an upper limit of mismatch among homologous chromosomes for CO formation. SVs were shown to be correlated with CO suppression, and their type and size were not found to influence that effect. The joint act of methylation and SVs was associated with the location of coldspots in barley, and the weight of their relative effect depends on the genomic region. Our findings suggest that recombination in barley is highly predictable, occurring mostly in multiple short sections located in proximity to genes and being modulated by local levels of methylation and SV load.</p>","PeriodicalId":233,"journal":{"name":"The Plant Journal","volume":"128 1","pages":"e71171"},"PeriodicalIF":6.2,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13655489/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149163453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A WHY1–NADK3–PEX5 module confers drought tolerance by maintaining peroxisomal ROS homeostasis in Brassica napus","authors":"Jiaqi Yan,&nbsp;Zhaoyang Qu,&nbsp;Chao Wang,&nbsp;Ze Tian,&nbsp;Lieqiong Kuang,&nbsp;Yu Mu,&nbsp;Hanzhong Wang,&nbsp;Xiaoling Dun","doi":"10.1111/tpj.71124","DOIUrl":"10.1111/tpj.71124","url":null,"abstract":"<p>Drought severely limits rapeseed productivity, but the role of NAD kinase in this process remains unclear. Here, we identify BnaA07.NADK3 as a drought- and ABA-inducible peroxisomal NADK in <i>Brassica napus</i>. Overexpression of BnaA07.NADK3 enhanced drought tolerance, whereas CRISPR/Cas9-edited lines showed reduced drought tolerance. Mechanistically, overexpression of <i>BnaA07.NADK3</i> elevates NADK activity and NADPH accumulation, thereby promoting the scavenging of drought-induced reactive oxygen species (ROS). Transcriptome profiling of <i>BnaA07.NADK3</i>-overexpressing plants revealed significant enrichment of genes involved in ROS detoxification and root development. Both <i>in vivo</i> and <i>in vitro</i> assays demonstrate that BnaA07.NADK3 physically interacts with the peroxisomal import receptor BnaA03.PEX5 (Peroxin 5), suggesting that BnaA07.NADK3 is associated with the peroxisomal protein import machinery required for maintaining ROS homeostasis under stress. In addition, BnaC08.WHY1 directly binds a conserved TTTTTGAC element in the <i>BnaA07.NADK3</i> promoter and activates its transcription. In summary, our findings uncover a previously unrecognized WHY1–NADK3–PEX5 regulatory module that integrates plastid retrograde signaling, peroxisomal redox metabolism, and drought adaptation in <i>Brassica napus</i>, providing promising targets for molecular breeding of drought-tolerant rapeseed cultivars.</p>","PeriodicalId":233,"journal":{"name":"The Plant Journal","volume":"127 6","pages":""},"PeriodicalIF":6.2,"publicationDate":"2026-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13627963/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149101750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GRF1 fine-tunes the copper-responsive transcription module of CPK3-bHLH107 by manipulating interaction and phosphorylation","authors":"Yue Yu,&nbsp;Haoran Xia,&nbsp;Ran Dong,&nbsp;Haifeng Liu,&nbsp;Xiangsong Chen,&nbsp;Zhaohui Chu","doi":"10.1111/tpj.71150","DOIUrl":"10.1111/tpj.71150","url":null,"abstract":"<p>Previously, the crucial role of calcium-dependent protein kinase 3 (CPK3) in Cu²⁺-triggered immunity (CuTI) has been established in Arabidopsis. CPK3 promotes the phosphorylation of basic helix–loop–helix 107 (bHLH107), thereby activating the expression of <i>1-aminocyclopropanecarboxylic acid synthesis 8</i> (<i>ACS8</i>) and downstream defense responses. However, the precise mechanisms underlying the fine-tuning of CPK3-mediated phosphorylation of bHLH107 remain unclear. To elucidate the mechanism underlying the inactivation of the CPK3-bHLH107 module, we identified a 14-3-3 protein, GRF1 (GF14χ), among candidate bHLH107 interactors. Notably, the interaction between GRF1 and bHLH107 was weaker following Cu²⁺ treatment than under control conditions. In <i>grf1</i> mutant plants, the transcript level of <i>ACS8</i> was slightly increased, concomitant with a modest increase in resistance to <i>Pst</i> DC3000. GRF1 interacts with both CPK3 and bHLH107 to maintain an ‘OFF’ state. Cu²⁺ mediates the phosphorylation of CPK3, attenuating its interaction with GRF1 and promoting its dissociation from GRF1. Subsequently, CPK3 phosphorylates bHLH107 and GRF1, thereby switching the immune response to the ‘ON’ state. Furthermore, wild-type GRF1, the quadruple phospho-defective mutant GRF1^{S72/88/125/156A} and the quadruple phosphomimetic mutant GRF1 ^{S72/88/125/156D} directly interact with unphosphorylated bHLH107, but not with the double phosphomimetic mutant protein bHLH107^S62/72D. We also revealed that GRF1 attenuates CPK3 kinase activity. Collectively, our findings indicated that CuTI is precisely orchestrated through GRF1-mediated modulation of the CPK3-bHLH107 module in Arabidopsis.</p>","PeriodicalId":233,"journal":{"name":"The Plant Journal","volume":"127 6","pages":""},"PeriodicalIF":6.2,"publicationDate":"2026-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13627851/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149101747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A COBRA-like protein ACL83 acts downstream of transcription factor ROC5 to control abaxial leaf curling in rice","authors":"Congping Chen,&nbsp;Rui Li,&nbsp;Jiahao Deng,&nbsp;Hongshan Zhang,&nbsp;Dan Liu,&nbsp;Yongkang Xiao,&nbsp;Junjie Liu,&nbsp;Hao Shu,&nbsp;Yue Liu,&nbsp;Xiaorong Yang,&nbsp;Jia Guo,&nbsp;Ying Zhong,&nbsp;Bin Yang,&nbsp;Changhui Sun,&nbsp;Xiaojian Deng,&nbsp;Pingrong Wang","doi":"10.1111/tpj.71144","DOIUrl":"10.1111/tpj.71144","url":null,"abstract":"<p>Leaf rolling is considered an important agronomic trait in rice (<i>Oryza sativa</i>). Moderate leaf rolling contributes to erect leaves and a compact plant architecture, thereby improving photosynthetic efficiency and grain yield. However, the molecular mechanisms regulating leaf rolling remain incompletely understood. In this study, we isolated an <i>acl83</i> mutant in <i>indica</i> rice, which exhibits abaxially curled leaves due to increased area of bulliform cells. Map-based cloning and MutMap analysis revealed the candidate gene <i>LOC_Os05g32110</i> (<i>ACL83</i>) encoding a COBRA-like protein. Complementation and CRISPR/Cas9 knockout assays confirmed that <i>ACL83</i> is responsible for the mutant phenotype of <i>acl83</i>. <i>ACL83</i> was constitutively expressed, and its encoded protein was localized to the plasma membrane. Furthermore, the transcription factor ROC5 directly bound to the promoter of <i>ACL83</i> to activate <i>ACL83</i> expression. Meanwhile, the <i>acl83</i>/<i>roc5</i> double mutant exhibited an abaxially curled leaf phenotype similar to that of the <i>acl83</i> single mutant, suggesting that <i>ACL83</i> is a downstream target gene of <i>ROC5</i>. Collectively, our findings revealed a distinct ROC5-ACL83 genetic pathway in which the COBRA-like protein ACL83 functions downstream of ROC5 to control abaxial leaf rolling in rice by regulating cell expansion. This work provides insight into the role of COBRA-like proteins in the regulation of leaf morphogenesis.</p>","PeriodicalId":233,"journal":{"name":"The Plant Journal","volume":"127 6","pages":""},"PeriodicalIF":6.2,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13618896/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149072993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Haplotype-resolved autotetraploid genome of Dioscorea nipponica provides insights into recent polyploidization, metabolic rewiring, and environmental adaptation","authors":"Shan-Shan Li,&nbsp;Xiao-Qin Sun,&nbsp;Yu Feng,&nbsp;Ke Hu,&nbsp;Pan Li,&nbsp;Yu Liu,&nbsp;Jun-Hao Gu,&nbsp;Min Chen,&nbsp;Rui-Sen Lu","doi":"10.1111/tpj.71153","DOIUrl":"10.1111/tpj.71153","url":null,"abstract":"<p>Whole-genome duplication (WGD, or polyploidization) is a major evolutionary force in plants, yet the genomic, transcriptional, and metabolic consequences of autopolyploidy remain less understood than those of allopolyploidy. <i>Dioscorea nipponica</i>, a medicinal species producing diosgenin-type steroidal saponins, harbors both diploid and autopolyploid populations, providing a unique system to investigate these processes. Here, we present a haplotype-resolved, chromosome-scale genome assembly of autotetraploid <i>D. nipponica</i> (2<i>n</i> = 4<i>x</i> = 40). Comparative and population genomic analyses indicate a single, recent autotetraploid origin (&lt;1.63 Ma), after the divergence of its diploid ancestors (~2.5–2.9 Ma), coinciding with Pliocene–Pleistocene climatic shifts that may have promoted population isolation and genome duplication. The four haplotypes exhibit high average nucleotide identity, extensive synteny and similar global gene expression, with pervasive allele loss (~32% of genes) and widespread allelic transcriptional suppression (~60% of expressed tetrads), together buffering dosage effects. Metabolomic profiling reveals a metabolic trade-off in rhizomes, with autotetraploids accumulating higher flavonoids but lower diosgenin-type steroidal saponins than diploids, potentially enhancing reproductive fitness and adaptation to marginal environments. This shift is supported by expanded flavonoid gene families (e.g., PAL, CHS), some exhibiting positive dosage effects, whereas diosgenin pathway genes (e.g., CYP90, CYP94) remain copy number stable and mostly show negative dosage effects in autotetraploids. Selective sweep analysis further identified genes linked to genome stability (e.g., <i>AtTOP3α</i>, <i>AtDMC1</i>) and abiotic stress response, crucial for polyploid establishment. Overall, these findings offer novel insights into how autopolyploidy shapes gene expression, metabolic evolution, and ecological adaptation, with implications for the conservation and utilization of this medicinally important species.</p>","PeriodicalId":233,"journal":{"name":"The Plant Journal","volume":"127 6","pages":""},"PeriodicalIF":6.2,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13618807/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149073042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Moderate overexpression of PROTON GRADIENT REGULATION 5 improves photosynthetic performance and plant growth under fluctuating low light in Arabidopsis thaliana","authors":"Keiichiro Tanigawa,&nbsp;Hiromasa Kodama,&nbsp;Yuki Okegawa,&nbsp;Toshiharu Shikanai,&nbsp;Wataru Yamori","doi":"10.1111/tpj.71120","DOIUrl":"10.1111/tpj.71120","url":null,"abstract":"<p>Cyclic electron transport around photosystem I (PSI) plays an important role in regulating photosynthesis by balancing ATP/NADPH production and maintaining PSI function under fluctuating light. Although PGR5-dependent photosynthetic regulation has been extensively studied under high or fluctuating light, its physiological significance under prolonged low irradiance interrupted by transient increases in light remains less well understood. Here, we analyzed <i>Arabidopsis thaliana</i> lines with different levels of PGR5 accumulation to investigate how PGR5 abundance influences photosynthetic regulation and plant performance under controlled fluctuating light conditions. Moderate PGR5 accumulation was associated with faster photosynthetic induction, improved PSI redox regulation, and greater biomass accumulation under the 100 μmol photons m⁻² s⁻¹ fluctuating light regime. In contrast, the absence of PGR5 severely impaired photosynthetic performance, particularly under the 600 μmol photons m⁻² s⁻¹ fluctuating light regime, whereas excessively high PGR5 accumulation did not provide additional physiological benefits. These results indicate that photosynthetic responses varied according to PGR5 abundance, but the relationship was not simply proportional across all genotypes. Our findings demonstrate that maintaining an appropriate level of PGR5 is important for efficient photosynthetic regulation under fluctuating light conditions. This study provides new physiological insights into the role of PGR5 under dynamic light environments and establishes a framework for future studies aimed at optimizing photosynthesis under naturally fluctuating irradiance.</p>","PeriodicalId":233,"journal":{"name":"The Plant Journal","volume":"127 6","pages":""},"PeriodicalIF":6.2,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13620446/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149072957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tissue-specific recombination-activated clonal and inducible transcription (TRAC-IT) enables controlled gene activation in stably marked tissues","authors":"Tristan Wijsman,&nbsp;Jana Wittmer,&nbsp;Robert Winter,&nbsp;Teun Bruins,&nbsp;Arjan van Zeijl,&nbsp;Harm Nijveen,&nbsp;Ben Scheres,&nbsp;Renze Heidstra","doi":"10.1111/tpj.71151","DOIUrl":"10.1111/tpj.71151","url":null,"abstract":"<p>Chemically inducible gene expression systems provide temporal control of transgene activation and therefore represent powerful and widely used tools in plant research. When driven by a cell-type-specific promoter, these systems additionally offer spatial control. However, continued transgene activity is necessarily linked to the preservation of that particular cell type, which might be lost as cells (de)differentiate. To overcome this, we present Tissue-specific Recombination-Activated Clonal and Inducible Transcription (TRAC-IT), a two-step system that uncouples inducible gene expression from cell identity. In the first step, a tissue-specific expressed CRE-GR recombinase is activated upon dexamethasone application, triggering loxP recombination and thereby generating tissue-specific clones of cells expressing <i>YFP</i> and <i>XVE</i>. YFP marks the clone and the XVE <i>trans</i>-activator allows inducible expression of downstream genes within the clone. In the second step, a subsequent β-estradiol application activates XVE to induce transgene expression exclusively within these YFP-marked clones. Because the inducibility of the transgenes becomes genomically anchored, it is maintained upon cell division and/or identity change. TRAC-IT is compatible with Golden Gate cloning, providing simple variation of tissue-specific promoters and transgenes. We show that TRAC-IT supports inducible and controlled tissue-specific clone formation, and that transgenes can be specifically induced within these clones. We employed TRAC-IT to demonstrate that epidermal cells in the root meristem can be persuaded to regenerate somatic embryos through clone-based induction of <i>PLT1</i> and <i>WOX5</i>. Thus, TRAC-IT offers a versatile tool that provides new technical possibilities to explore the mechanisms driving plant development in a stable tissue-specific fashion.</p>","PeriodicalId":233,"journal":{"name":"The Plant Journal","volume":"127 6","pages":""},"PeriodicalIF":6.2,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13617364/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149068943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular mechanisms underlying seed enlargement mediated by seed coat development in autotetraploid castor bean","authors":"Dan He,&nbsp;Tianlong Yang,&nbsp;Xianxing Chen,&nbsp;Xueyong Xu,&nbsp;Chen Liu,&nbsp;Anmin Yu,&nbsp;Bing Han,&nbsp;Aizhong Liu,&nbsp;Jian Wu","doi":"10.1111/tpj.71146","DOIUrl":"10.1111/tpj.71146","url":null,"abstract":"<p>Polyploids, particularly synthetic lines, often produce larger seeds than their diploid progenitors. However, little is known regarding the role of seed coat development in the larger seeds formation in polyploid plants. Here, we investigated the cellular and molecular basis by which seed coat development mediates seed enlargement in the oilseed crop castor bean (<i>Ricinus communis</i> L.) following homologous chromosome doubling. We found that seeds of autotetraploid castor bean, including seed length, width, thickness and hundred-seed weight, were significantly greater than those of diploids. Histological analysis further revealed that the enlarged seeds were associated with increased seed coat cell area. At the transcriptome level, we showed that genome doubling led to stage-specific and non-linear transcriptional changes. A total of 6043 non-redundant differentially expressed genes (DEGs) were identified between tetraploid and diploid seed coats. Among them, several key genes related to cell expansion and cell wall loosening (e.g. <i>RcEXPA1</i>/<i>5</i>/<i>9</i>/<i>12</i>/<i>15</i> and <i>RcEXLA1</i>, <i>RcEXTs</i>, <i>RcELP</i>, <i>RcCESA4/7/8</i>, <i>RcXYL1</i>, and <i>RcXTH15</i>/<i>27</i>/<i>30</i>) were significantly up-regulated in tetraploids, consistent with enhanced seed coat expansion. In addition, lignin biosynthesis-related genes (<i>RcPAL1</i>, <i>RcCOMT1</i>, <i>Rc4CL2</i>, <i>RcCSE</i>, <i>RcC4H</i>, <i>RcCCRs</i>, <i>RcCADs</i>, <i>RcCCoAOMT1</i>, and <i>RcHCT</i>) were significantly down-regulated in tetraploids, which may facilitate seed coat cell enlargement. The stage-specific DEGs in the indole-3-acetic acid (IAA), gibberellin, and brassinosteroid signaling pathways (<i>RcIAA3</i>/<i>13</i>/<i>16</i>/<i>26</i>/<i>27</i>, <i>RcRGL2</i>, and <i>RcBSK6</i>) may contribute to regulating seed coat cell development. Importantly, co-expression analysis together with yeast one-hybrid, electrophoretic mobility shift assay, and dual-luciferase reporter (DLR) assays showed that RcPDF2 bound to two L1-box elements in the <i>RcEXLA1</i> promoter and increased its promoter activity, suggesting that RcPDF2 contributes to seed size determination by modulating seed coat cell expansion. Collectively, our study provides important insights into the underlying molecular basis of gene dosage effects on seed size formation in autopolyploid plants, thereby laying a solid foundation for enhancing yield in castor bean through polyploid breeding.</p>","PeriodicalId":233,"journal":{"name":"The Plant Journal","volume":"127 6","pages":""},"PeriodicalIF":6.2,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13618894/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149072969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constitutive AtRD29A expression reveals divergent BpCBF3 regulatory mechanisms in birch","authors":"Mengyan Ge,&nbsp;Xinyu Wang,&nbsp;Lili Hou,&nbsp;Guifeng Liu,&nbsp;Zhimin Zheng","doi":"10.1111/tpj.71121","DOIUrl":"https://doi.org/10.1111/tpj.71121","url":null,"abstract":"<p>Abiotic stress resistance in plants is often associated with growth retardation. To address this limitation, stress-inducible promoters can be used to generate plants that exhibit both rapid growth and high stress resistance. <i>RD29A</i> (Response to Desiccation 29A) is a widely used stress-inducible promoter in <i>Arabidopsis thaliana</i> (<i>AtRD29A</i>) that can be activated by multiple factors including NaCl, ABA, and low temperature. Specifically, under cold stress, it is induced through the response to C-repeat/DREB binding factors (<i>CBFs</i>). In this study, we identified five <i>CBF3</i> homologous genes—<i>BpCBF3e</i>, <i>BpCBF3b</i>, <i>BpCBF3d</i>, <i>BpCBF3c</i>, and <i>BpCBF3a—</i>in birch (<i>Betula platyphylla</i>), but did not detect an <i>RD29A</i> homolog. We proposed <i>BpCBF3d</i> to be the functional <i>CBF</i> because its expression is strongly regulated by circadian rhythm and cold stress, and it activates downstream cold response marker genes. To confirm this hypothesis, we performed Y1H assays and generated <i>BpCBF3d</i> overexpression lines driven by two different promoters—<i>p35S</i> and <i>pRD29A</i>. Notably, we found that <i>BpCBF3d</i> did not bind to the <i>AtRD29A</i> promoter, whereas <i>BpCBF3e</i>, <i>BpCBF3b</i>, <i>BpCBF3c</i>, and <i>BpCBF3a</i> bound strongly, resulting in constitutive expression of heterologous <i>AtRD29A</i> in birch. This study provides new molecular tools for breeding forest trees with enhanced resilience to environmental change.</p>","PeriodicalId":233,"journal":{"name":"The Plant Journal","volume":"127 6","pages":""},"PeriodicalIF":6.2,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/tpj.71121","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149048237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}