{"title":"A matter of quantity: The effect of chloroplast stromal phosphate levels on photosynthetic efficiency.","authors":"Pablo Ignacio Calzadilla","doi":"10.1093/plphys/kiae307","DOIUrl":"10.1093/plphys/kiae307","url":null,"abstract":"","PeriodicalId":20101,"journal":{"name":"Plant Physiology","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11376378/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141158761","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}
Lena Frenzke, Franco Röckel, Torsten Wenke, Florian Schwander, Konrad Grützmann, Julia Naumann, Falk Zakrzewski, Tom Heinekamp, Maria Maglione, Anja Wenke, Anja Kögler, Eva Zyprian, Andreas Dahl, Franz Förster, Reinhard Töpfer, Stefan Wanke
Veraison marks the transition from berry growth to berry ripening and is a crucial phenological stage in grapevine (Vitis vinifera): the berries become soft and begin to accumulate sugars, aromatic substances, and, in red cultivars, anthocyanins for pigmentation, while the organic acid levels begin to decrease. These changes determine the potential quality of wine. However, rising global temperatures lead to earlier flowering and ripening, which strongly influence wine quality. Here, we combined genotyping-by-sequencing with a bioinformatics pipeline on ∼150 F1 genotypes derived from a cross between the early ripening variety "Calardis Musqué" and the late-ripening variety "Villard Blanc". Starting from 20,410 haplotype-based markers, we generated a high-density genetic map and performed a quantitative trait locus analysis based on phenotypic datasets evaluated over 20 yrs. Through locus-specific marker enrichment and recombinant screening of ∼1,000 additional genotypes, we refined the originally postulated 5-mb veraison locus, Ver1, on chromosome 16 to only 112 kb, allowing us to pinpoint the ethylene response factor VviERF027 (VCost.v3 gene ID: Vitvi16g00942, CRIBIv1 gene ID: VIT_16s0100g00400) as veraison candidate gene. Furthermore, the early veraison allele could be traced back to a clonal "Pinot" variant first mentioned in the seventeenth century. "Pinot Precoce Noir" passed this allele over "Madeleine Royale" to the maternal grandparent "Bacchus Weiss" and, ultimately, to the maternal parent "Calardis Musqué". Our findings are crucial for ripening time control, thereby improving wine quality, and for breeding grapevines adjusted to climate change scenarios that have a major impact on agro-ecosystems in altering crop plant phenology.
{"title":"Genotyping-by-sequencing-based high-resolution mapping reveals a single candidate gene for the grapevine veraison locus Ver1.","authors":"Lena Frenzke, Franco Röckel, Torsten Wenke, Florian Schwander, Konrad Grützmann, Julia Naumann, Falk Zakrzewski, Tom Heinekamp, Maria Maglione, Anja Wenke, Anja Kögler, Eva Zyprian, Andreas Dahl, Franz Förster, Reinhard Töpfer, Stefan Wanke","doi":"10.1093/plphys/kiae272","DOIUrl":"10.1093/plphys/kiae272","url":null,"abstract":"<p><p>Veraison marks the transition from berry growth to berry ripening and is a crucial phenological stage in grapevine (Vitis vinifera): the berries become soft and begin to accumulate sugars, aromatic substances, and, in red cultivars, anthocyanins for pigmentation, while the organic acid levels begin to decrease. These changes determine the potential quality of wine. However, rising global temperatures lead to earlier flowering and ripening, which strongly influence wine quality. Here, we combined genotyping-by-sequencing with a bioinformatics pipeline on ∼150 F1 genotypes derived from a cross between the early ripening variety \"Calardis Musqué\" and the late-ripening variety \"Villard Blanc\". Starting from 20,410 haplotype-based markers, we generated a high-density genetic map and performed a quantitative trait locus analysis based on phenotypic datasets evaluated over 20 yrs. Through locus-specific marker enrichment and recombinant screening of ∼1,000 additional genotypes, we refined the originally postulated 5-mb veraison locus, Ver1, on chromosome 16 to only 112 kb, allowing us to pinpoint the ethylene response factor VviERF027 (VCost.v3 gene ID: Vitvi16g00942, CRIBIv1 gene ID: VIT_16s0100g00400) as veraison candidate gene. Furthermore, the early veraison allele could be traced back to a clonal \"Pinot\" variant first mentioned in the seventeenth century. \"Pinot Precoce Noir\" passed this allele over \"Madeleine Royale\" to the maternal grandparent \"Bacchus Weiss\" and, ultimately, to the maternal parent \"Calardis Musqué\". Our findings are crucial for ripening time control, thereby improving wine quality, and for breeding grapevines adjusted to climate change scenarios that have a major impact on agro-ecosystems in altering crop plant phenology.</p>","PeriodicalId":20101,"journal":{"name":"Plant Physiology","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11376399/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140922847","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}
Ouad Soltani, Moritz Jöst, Iris Hoffie, Götz Hensel, Christian Kappel, Gali Prag, Sarah McKim, Jochen Kumlehn, Michael Lenhard
Establishment of final leaf size in plants relies on the precise regulation of 2 interconnected processes, cell division and cell expansion. The barley (Hordeum vulgare) protein BROAD LEAF1 (BLF1) limits cell proliferation and leaf growth in the width direction. However, how the levels of this potent repressor of leaf growth are controlled remains unclear. Here, we used a yeast 2-hybrid screen to identify the BLF1-INTERACTING RING/U-BOX 1 (BIR1) E3 ubiquitin ligase that interacts with BLF1 and confirmed the interaction of the 2 proteins in planta. Inhibiting the proteasome caused overaccumulation of a BLF1-eGFP fusion protein when co-expressed with BIR1, and an in vivo ubiquitination assay in bacteria confirmed that BIR1 can mediate ubiquitination of BLF1 protein. Consistent with regulation of endogenous BLF1 in barley by proteasomal degradation, inhibition of the proteasome in BLF1-vYFP-expressing barley plants caused an accumulation of the BLF1 protein. The BIR1 protein co-localized with BLF1 in nuclei and appeared to reduce BLF1 protein levels. Analysis of bir1-1 knockout mutants suggested the involvement of BIR1 in leaf growth control, although mainly on leaf length. Together, our results suggest that proteasomal degradation, in part mediated by BIR1, helps fine-tune BLF1 protein levels in barley.
{"title":"RING/U-box E3 protein BIR1 interacts with and ubiquitinates barley growth repressor BROAD LEAF1.","authors":"Ouad Soltani, Moritz Jöst, Iris Hoffie, Götz Hensel, Christian Kappel, Gali Prag, Sarah McKim, Jochen Kumlehn, Michael Lenhard","doi":"10.1093/plphys/kiae315","DOIUrl":"10.1093/plphys/kiae315","url":null,"abstract":"<p><p>Establishment of final leaf size in plants relies on the precise regulation of 2 interconnected processes, cell division and cell expansion. The barley (Hordeum vulgare) protein BROAD LEAF1 (BLF1) limits cell proliferation and leaf growth in the width direction. However, how the levels of this potent repressor of leaf growth are controlled remains unclear. Here, we used a yeast 2-hybrid screen to identify the BLF1-INTERACTING RING/U-BOX 1 (BIR1) E3 ubiquitin ligase that interacts with BLF1 and confirmed the interaction of the 2 proteins in planta. Inhibiting the proteasome caused overaccumulation of a BLF1-eGFP fusion protein when co-expressed with BIR1, and an in vivo ubiquitination assay in bacteria confirmed that BIR1 can mediate ubiquitination of BLF1 protein. Consistent with regulation of endogenous BLF1 in barley by proteasomal degradation, inhibition of the proteasome in BLF1-vYFP-expressing barley plants caused an accumulation of the BLF1 protein. The BIR1 protein co-localized with BLF1 in nuclei and appeared to reduce BLF1 protein levels. Analysis of bir1-1 knockout mutants suggested the involvement of BIR1 in leaf growth control, although mainly on leaf length. Together, our results suggest that proteasomal degradation, in part mediated by BIR1, helps fine-tune BLF1 protein levels in barley.</p>","PeriodicalId":20101,"journal":{"name":"Plant Physiology","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141238118","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}
Rayyan Khan, Fei Gao, Kashif Khan, Muhammad Ali Shah, Haseeb Ahmad, Zhu Peng Fan, Xun Bo Zhou
Salt stress presents a major obstacle to maize (Zea mays L.) production globally, impeding its growth and development. In this study, we aimed to identify salt-tolerant maize varieties through evaluation using multivariate analysis and shed light on the role of ionome, antioxidant capacity, and autophagy in salt tolerance. We investigated multiple growth indices, including shoot fresh weight, shoot dry weight, plant height, chlorophyll content, electrolyte leakage, potassium and sodium contents, and potassium-to-sodium ratio, in 20 maize varieties at the V3 stage under salt stress (200 mm NaCl). The results showed significant differences in the growth indices, accompanied by a wide range in their coefficient of variation, suggesting their suitability for screening salt tolerance. Based on D values, clustering analysis categorized the 20 varieties into 4 distinct groups. TG88, KN20, and LR888 (group I) emerged as the most salt-tolerant varieties, while YD9, XD903, and LH151 (group IV) were identified as the most sensitive. TG88 showcased nutrient preservation and redistribution under salt stress, surpassing YD9. It maintained nitrogen and iron levels in roots, while YD9 experienced decreases. TG88 redistributed more nitrogen, zinc, and potassium to its leaves, outperforming YD9. TG88 preserved sulfur levels in both roots and leaves, unlike YD9. Additionally, TG88 demonstrated higher enzymatic antioxidant capacity (superoxide dismutase, peroxidase, ascorbate peroxidase, and glutathione reductase) at both the enzyme and gene expression levels, upregulation of autophagy-related (ATG) genes (ZmATG6, ZmATG8a, and ZmATG10), and increased autophagic activity. Overall, this study offers insights into accurate maize varieties evaluation methods and the physiological mechanisms underlying salt tolerance and identifies promising materials for further research.
{"title":"Evaluation of maize varieties via multivariate analysis: Roles of ionome, antioxidants, and autophagy in salt tolerance.","authors":"Rayyan Khan, Fei Gao, Kashif Khan, Muhammad Ali Shah, Haseeb Ahmad, Zhu Peng Fan, Xun Bo Zhou","doi":"10.1093/plphys/kiae335","DOIUrl":"10.1093/plphys/kiae335","url":null,"abstract":"<p><p>Salt stress presents a major obstacle to maize (Zea mays L.) production globally, impeding its growth and development. In this study, we aimed to identify salt-tolerant maize varieties through evaluation using multivariate analysis and shed light on the role of ionome, antioxidant capacity, and autophagy in salt tolerance. We investigated multiple growth indices, including shoot fresh weight, shoot dry weight, plant height, chlorophyll content, electrolyte leakage, potassium and sodium contents, and potassium-to-sodium ratio, in 20 maize varieties at the V3 stage under salt stress (200 mm NaCl). The results showed significant differences in the growth indices, accompanied by a wide range in their coefficient of variation, suggesting their suitability for screening salt tolerance. Based on D values, clustering analysis categorized the 20 varieties into 4 distinct groups. TG88, KN20, and LR888 (group I) emerged as the most salt-tolerant varieties, while YD9, XD903, and LH151 (group IV) were identified as the most sensitive. TG88 showcased nutrient preservation and redistribution under salt stress, surpassing YD9. It maintained nitrogen and iron levels in roots, while YD9 experienced decreases. TG88 redistributed more nitrogen, zinc, and potassium to its leaves, outperforming YD9. TG88 preserved sulfur levels in both roots and leaves, unlike YD9. Additionally, TG88 demonstrated higher enzymatic antioxidant capacity (superoxide dismutase, peroxidase, ascorbate peroxidase, and glutathione reductase) at both the enzyme and gene expression levels, upregulation of autophagy-related (ATG) genes (ZmATG6, ZmATG8a, and ZmATG10), and increased autophagic activity. Overall, this study offers insights into accurate maize varieties evaluation methods and the physiological mechanisms underlying salt tolerance and identifies promising materials for further research.</p>","PeriodicalId":20101,"journal":{"name":"Plant Physiology","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141311401","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":"Plant Physiology is recruiting Assistant Features Editors to start in 2025 and 2026.","authors":"Yunde Zhao, Mary Williams","doi":"10.1093/plphys/kiae304","DOIUrl":"10.1093/plphys/kiae304","url":null,"abstract":"","PeriodicalId":20101,"journal":{"name":"Plant Physiology","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11376395/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141311403","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":"Trehalose or not-trehalose: The question of direct vs. indirect transcriptional responses to the sugar trehalose-6-phosphate.","authors":"Thu M Tran, Kyle W Swentowsky","doi":"10.1093/plphys/kiae306","DOIUrl":"10.1093/plphys/kiae306","url":null,"abstract":"","PeriodicalId":20101,"journal":{"name":"Plant Physiology","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11376377/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141184492","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}
Sclerotinia disease is one of the most devastating fungal diseases worldwide, as it reduces the yields of many economically important crops. Pathogen-secreted effectors play crucial roles in infection processes. However, key effectors of Ciboria shiraiana, the pathogen primarily responsible for sclerotinia disease in mulberry (Morus spp.), remain poorly understood. In this study, we identified and functionally characterized the effector Cs02526 in C. shiraiana and found that Cs02526 could induce cell death in a variety of plants. Moreover, Cs02526-induced cell death was mediated by the central immune regulator brassinosteroid insensitive 1-associated receptor kinase 1, dependent on a 67-amino acid fragment. Notably, Cs02526 homologs were widely distributed in hemibiotrophic and necrotrophic phytopathogenic fungi, but the homologs failed to induce cell death in plants. Pretreatment of plants with recombinant Cs02526 protein enhanced resistance against both C. shiraiana and Sclerotinia sclerotiorum. Furthermore, the pathogenicity of C. shiraiana was diminished upon spraying plants with synthetic dsRNA-Cs02526. In conclusion, our findings highlight the cell death-inducing effector Cs02526 as a potential target for future biological control strategies against plant diseases.
{"title":"Effector Cs02526 from Ciboria shiraiana induces cell death and modulates plant immunity.","authors":"Shuai Zhang, Ruolan Li, Wei Fan, Xuefei Chen, Shuman Liu, Panpan Zhu, Xiaohui Gu, Shuchang Wang, Aichun Zhao","doi":"10.1093/plphys/kiae286","DOIUrl":"10.1093/plphys/kiae286","url":null,"abstract":"<p><p>Sclerotinia disease is one of the most devastating fungal diseases worldwide, as it reduces the yields of many economically important crops. Pathogen-secreted effectors play crucial roles in infection processes. However, key effectors of Ciboria shiraiana, the pathogen primarily responsible for sclerotinia disease in mulberry (Morus spp.), remain poorly understood. In this study, we identified and functionally characterized the effector Cs02526 in C. shiraiana and found that Cs02526 could induce cell death in a variety of plants. Moreover, Cs02526-induced cell death was mediated by the central immune regulator brassinosteroid insensitive 1-associated receptor kinase 1, dependent on a 67-amino acid fragment. Notably, Cs02526 homologs were widely distributed in hemibiotrophic and necrotrophic phytopathogenic fungi, but the homologs failed to induce cell death in plants. Pretreatment of plants with recombinant Cs02526 protein enhanced resistance against both C. shiraiana and Sclerotinia sclerotiorum. Furthermore, the pathogenicity of C. shiraiana was diminished upon spraying plants with synthetic dsRNA-Cs02526. In conclusion, our findings highlight the cell death-inducing effector Cs02526 as a potential target for future biological control strategies against plant diseases.</p>","PeriodicalId":20101,"journal":{"name":"Plant Physiology","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11376374/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140945672","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}
Jaspreet Sandhu, Larissa Irvin, Anil Kumar Chandaran, Shohei Oguro, Puneet Paul, Balpreet Dhatt, Waseem Hussain, Shannon S Cunningham, Cherryl O Quinones, Argelia Lorence, Maria Arlene Adviento-Borbe, Paul Staswick, Gota Morota, Harkamal Walia
Global nighttime temperatures are rising at twice the rate of daytime temperatures and pose a challenge for rice (Oryza sativa) production. High nighttime temperature (HNT) stress affects rice yield by reducing grain weight, size, and fertility. Although the genes associated with these yield parameters have been identified and characterized under normal temperatures, the genetic basis of grain weight regulation under HNT stress remains less explored. We examined the natural variation for rice single grain weight (SGW) under HNT stress imposed during grain development. A genome-wide association analysis identified several loci associated with grain weight under HNT stress. A locus, SGW1, specific to HNT conditions resolved to LONELY GUY-Like 1 (LOGL1), which encodes a putative cytokinin-activation enzyme. We demonstrated that LOGL1 contributes to allelic variation at SGW1. Accessions with lower LOGL1 transcript abundance had higher grain weight under HNT. This was supported by the higher grain weight of logl1-mutants relative to the wild type under HNT. Compared to logl1-mutants, LOGL1 over-expressers showed increased sensitivity to HNT. We showed that LOGL1 regulates the thiamin biosynthesis pathway, which is under circadian regulation, which in turn is likely perturbed by HNT stress. These findings provide a genetic source to enhance rice adaptation to warming night temperatures and improve our mechanistic understanding of HNT stress tolerance pathways.
{"title":"Natural variation in LONELY GUY-Like 1 regulates rice grain weight under warmer night conditions.","authors":"Jaspreet Sandhu, Larissa Irvin, Anil Kumar Chandaran, Shohei Oguro, Puneet Paul, Balpreet Dhatt, Waseem Hussain, Shannon S Cunningham, Cherryl O Quinones, Argelia Lorence, Maria Arlene Adviento-Borbe, Paul Staswick, Gota Morota, Harkamal Walia","doi":"10.1093/plphys/kiae313","DOIUrl":"10.1093/plphys/kiae313","url":null,"abstract":"<p><p>Global nighttime temperatures are rising at twice the rate of daytime temperatures and pose a challenge for rice (Oryza sativa) production. High nighttime temperature (HNT) stress affects rice yield by reducing grain weight, size, and fertility. Although the genes associated with these yield parameters have been identified and characterized under normal temperatures, the genetic basis of grain weight regulation under HNT stress remains less explored. We examined the natural variation for rice single grain weight (SGW) under HNT stress imposed during grain development. A genome-wide association analysis identified several loci associated with grain weight under HNT stress. A locus, SGW1, specific to HNT conditions resolved to LONELY GUY-Like 1 (LOGL1), which encodes a putative cytokinin-activation enzyme. We demonstrated that LOGL1 contributes to allelic variation at SGW1. Accessions with lower LOGL1 transcript abundance had higher grain weight under HNT. This was supported by the higher grain weight of logl1-mutants relative to the wild type under HNT. Compared to logl1-mutants, LOGL1 over-expressers showed increased sensitivity to HNT. We showed that LOGL1 regulates the thiamin biosynthesis pathway, which is under circadian regulation, which in turn is likely perturbed by HNT stress. These findings provide a genetic source to enhance rice adaptation to warming night temperatures and improve our mechanistic understanding of HNT stress tolerance pathways.</p>","PeriodicalId":20101,"journal":{"name":"Plant Physiology","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11376391/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141184489","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}
Angiosperm trees usually develop tension wood (TW) in response to gravitational stimulation. TW comprises abundant gelatinous (G-) fibers with thick G-layers primarily composed of crystalline cellulose. Understanding the pivotal factors governing G-layer formation in TW fiber remains elusive. This study elucidates the role of a Populus trichocarpa COBRA family protein, PtrCOB3, in the G-layer formation of TW fibers. PtrCOB3 expression was upregulated, and its promoter activity was enhanced during TW formation. Comparative analysis with wild-type trees revealed that ptrcob3 mutants, mediated by Cas9/gRNA gene editing, were incapable of producing G-layers within TW fibers and showed severely impaired stem lift. Fluorescence immunolabeling data revealed a dearth of crystalline cellulose in the tertiary cell wall (TCW) of ptrcob3 TW fibers. The role of PtrCOB3 in G-layer formation is contingent upon its native promoter, as evidenced by the comparative phenotypic assessments of pCOB11::PtrCOB3, pCOB3::PtrCOB3, and pCOB3::PtrCOB11 transgenic lines in the ptrcob3 background. Overexpression of PtrCOB3 under the control of its native promoter expedited G-layer formation within TW fibers. We further identified 3 transcription factors that bind to the PtrCOB3 promoter and positively regulate its transcriptional levels. Alongside the primary TCW synthesis genes, these findings enable the construction of a 2-layer transcriptional regulatory network for the G-layer formation of TW fibers. Overall, this study uncovers mechanistic insight into TW formation, whereby a specific COB protein executes the deposition of cellulose, and consequently, G-layer formation within TW fibers.
被子植物树木通常会在重力刺激下形成张力木(TW)。张力木由丰富的胶状(G-)纤维组成,G-层很厚,主要由结晶纤维素构成。人们对影响 TW 纤维中 G 层形成的关键因素仍然缺乏了解。本研究阐明了杨树 COBRA 家族蛋白 PtrCOB3 在 TW 纤维 G 层形成过程中的作用。在 TW 形成过程中,PtrCOB3 表达上调,其启动子活性增强。与野生型树木的比较分析表明,由Cas9/gRNA基因编辑介导的ptrcob3突变体无法在TW纤维内形成G层,并表现出严重的茎举障碍。荧光免疫标记数据显示,ptrcob3 TW 纤维的三级细胞壁(TCW)中缺乏结晶纤维素。Ptrcob3 背景下的 pCOB11::PtrCOB3、pCOB3::PtrCOB3 和 pCOB3::PtrCOB11转基因品系的表型比较评估证明,PtrCOB3 在 G 层形成中的作用取决于其原生启动子。在 PtrCOB3 本源启动子的控制下,PtrCOB3 的过表达加速了 TW 纤维内 G 层的形成。我们进一步鉴定了与 PtrCOB3 启动子结合并正向调节其转录水平的三个转录因子。除了主要的 TCW 合成基因外,这些发现还为 TW 纤维 G 层的形成构建了一个双层转录调控网络。总之,这项研究揭示了 TW 形成的机理,即特定的 COB 蛋白执行纤维素的沉积,从而在 TW 纤维中形成 G 层。
{"title":"A COBRA family protein, PtrCOB3, contributes to gelatinous layer formation of tension wood fibers in poplar.","authors":"Wenjing Xu, Hao Cheng, Jiyao Cheng, Siran Zhu, Yongyao Cui, Chong Wang, Jianzhen Wu, Xingguo Lan, Yuxiang Cheng","doi":"10.1093/plphys/kiae328","DOIUrl":"10.1093/plphys/kiae328","url":null,"abstract":"<p><p>Angiosperm trees usually develop tension wood (TW) in response to gravitational stimulation. TW comprises abundant gelatinous (G-) fibers with thick G-layers primarily composed of crystalline cellulose. Understanding the pivotal factors governing G-layer formation in TW fiber remains elusive. This study elucidates the role of a Populus trichocarpa COBRA family protein, PtrCOB3, in the G-layer formation of TW fibers. PtrCOB3 expression was upregulated, and its promoter activity was enhanced during TW formation. Comparative analysis with wild-type trees revealed that ptrcob3 mutants, mediated by Cas9/gRNA gene editing, were incapable of producing G-layers within TW fibers and showed severely impaired stem lift. Fluorescence immunolabeling data revealed a dearth of crystalline cellulose in the tertiary cell wall (TCW) of ptrcob3 TW fibers. The role of PtrCOB3 in G-layer formation is contingent upon its native promoter, as evidenced by the comparative phenotypic assessments of pCOB11::PtrCOB3, pCOB3::PtrCOB3, and pCOB3::PtrCOB11 transgenic lines in the ptrcob3 background. Overexpression of PtrCOB3 under the control of its native promoter expedited G-layer formation within TW fibers. We further identified 3 transcription factors that bind to the PtrCOB3 promoter and positively regulate its transcriptional levels. Alongside the primary TCW synthesis genes, these findings enable the construction of a 2-layer transcriptional regulatory network for the G-layer formation of TW fibers. Overall, this study uncovers mechanistic insight into TW formation, whereby a specific COB protein executes the deposition of cellulose, and consequently, G-layer formation within TW fibers.</p>","PeriodicalId":20101,"journal":{"name":"Plant Physiology","volume":null,"pages":null},"PeriodicalIF":6.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141288434","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}