Pear ring rot, caused by the pathogenic fungi Botryosphaeria dothidea, seriously affects pear production. While the infection-induced reactive oxygen species (ROS) burst of infected plants limits the proliferation of B. dothidea during the early infection stage, high ROS levels can also contribute to their growth during the later necrotrophic infection stage. Therefore, it is important to understand how plants balance ROS levels and resistance to pathogenic B. dothidea during the later stage. In this study, we identified PbrChiA, a glycosyl hydrolases 18 (GH18) chitinase-encoding gene with high infection-induced expression, through a comparative transcriptome analysis. Artificial substitution, stable overexpression, and virus induced gene silencing (VIGS) experiments demonstrated that PbrChiA can positively regulate pear resistance as a secreted chitinase to break down B. dothidea mycelium in vitro and that overexpression of PbrChiA suppressed infection-induced ROS accumulation. Further analysis revealed that PbrChiA can bind to the ectodomain of PbrLYK1b2, and this interaction suppressed PbrLYK1b2-mediated chitin-induced ROS accumulation. Collectively, we propose that the combination of higher antifungal activity from abundant PbrChiA and lower ROS levels during later necrotrophic infection stage confer resistance of pear against B. dothidea.
{"title":"PbrChiA: a key chitinase of pear in response to <i>Botryosphaeria dothidea</i> infection by interacting with PbrLYK1b2 and down-regulating ROS accumulation.","authors":"Qiming Chen, Huizhen Dong, Qionghou Li, Xun Sun, Xin Qiao, Hao Yin, Zhihua Xie, Kaijie Qi, Xiaosan Huang, Shaoling Zhang","doi":"10.1093/hr/uhad188","DOIUrl":"https://doi.org/10.1093/hr/uhad188","url":null,"abstract":"<p><p>Pear ring rot, caused by the pathogenic fungi <i>Botryosphaeria dothidea</i>, seriously affects pear production. While the infection-induced reactive oxygen species (ROS) burst of infected plants limits the proliferation of <i>B. dothidea</i> during the early infection stage, high ROS levels can also contribute to their growth during the later necrotrophic infection stage. Therefore, it is important to understand how plants balance ROS levels and resistance to pathogenic <i>B. dothidea</i> during the later stage. In this study, we identified <i>PbrChiA</i>, a glycosyl hydrolases 18 (GH18) chitinase-encoding gene with high infection-induced expression, through a comparative transcriptome analysis. Artificial substitution, stable overexpression, and virus induced gene silencing (VIGS) experiments demonstrated that PbrChiA can positively regulate pear resistance as a secreted chitinase to break down <i>B. dothidea</i> mycelium <i>in vitro</i> and that overexpression of <i>PbrChiA</i> suppressed infection-induced ROS accumulation. Further analysis revealed that PbrChiA can bind to the ectodomain of PbrLYK1b2, and this interaction suppressed PbrLYK1b2-mediated chitin-induced ROS accumulation. Collectively, we propose that the combination of higher antifungal activity from abundant PbrChiA and lower ROS levels during later necrotrophic infection stage confer resistance of pear against <i>B. dothidea</i>.</p>","PeriodicalId":57479,"journal":{"name":"园艺研究(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10611555/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71415486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-19eCollection Date: 2023-10-01DOI: 10.1093/hr/uhad190
Jianhui Wang, Rui Xu, Shuangping Qiu, Weichun Wang, Fan Zheng
A homologous gene of basic-helix-loop-helix AtTT8 in Arabidopsis thaliana was identified in juice sac cells of pulp tissues from blood orange (Citrus sinensis cv 'Tarocco'), which was designated as CsTT8 in this study. Additionally, the mRNA levels of TT8 with the full-length open reading frame were significantly higher in 'Tarocco' than in mutant fruit lacking pigment in pulp or peel tissues. However, an alternative splicing transcript, Δ15-TT8, with the fourth exon skipped, was also identified from transcripts different in length from that in 'Tarocco'. The mRNA levels of Δ15-TT8 were higher in mutant fruit lacking pigment in pulp or peel tissues than in the wild type. Therefore, the TT8/Δ15-TT8 mRNA level ratio was found to be crucial for sufficient pigment in either pulp or peel tissues. TT8 from blood orange fruit demonstrated the capacity for nucleus localization and binding to other proteins. In contrast, Δ15-TT8, lacking the fourth exon, lost its ability to interact with RUBY1 and to localize at the nucleus. Using a dual luciferase reporter assay and transient overexpression in tobacco, we proved that two regulatory complexes formed by a functional TT8 with different MYB(v-myb avian myeloblastosis viral oncogene homolog)-type partners significantly promoted expression of an anthocyanin biosynthetic gene and a proton pumping gene, leading to anthocyanin and citrate production. Our findings suggest that TT8, rather than dysfunctional Δ15-TT8, is possibly involved in modulating anthocyanin biosynthesis and its transport into vacuoles by proton gradients. However, increased mRNA levels of the dysfunctional alternative splicing transcript may act as a negative feedback to downregulate TT8 expression and limit anthocyanin accumulation in blood oranges.
{"title":"<i>CsTT8</i> regulates anthocyanin accumulation in blood orange through alternative splicing transcription.","authors":"Jianhui Wang, Rui Xu, Shuangping Qiu, Weichun Wang, Fan Zheng","doi":"10.1093/hr/uhad190","DOIUrl":"https://doi.org/10.1093/hr/uhad190","url":null,"abstract":"<p><p>A homologous gene of basic-helix-loop-helix <i>AtTT8</i> in <i>Arabidopsis thaliana</i> was identified in juice sac cells of pulp tissues from blood orange (<i>Citrus sinensis</i> cv 'Tarocco'), which was designated as <i>CsTT8</i> in this study. Additionally, the mRNA levels of <i>TT8</i> with the full-length open reading frame were significantly higher in 'Tarocco' than in mutant fruit lacking pigment in pulp or peel tissues. However, an alternative splicing transcript, Δ15-<i>TT8</i>, with the fourth exon skipped, was also identified from transcripts different in length from that in 'Tarocco'. The mRNA levels of Δ15-<i>TT8</i> were higher in mutant fruit lacking pigment in pulp or peel tissues than in the wild type. Therefore, the <i>TT8</i>/Δ15-<i>TT8</i> mRNA level ratio was found to be crucial for sufficient pigment in either pulp or peel tissues. TT8 from blood orange fruit demonstrated the capacity for nucleus localization and binding to other proteins. In contrast, Δ15-TT8, lacking the fourth exon, lost its ability to interact with RUBY1 and to localize at the nucleus. Using a dual luciferase reporter assay and transient overexpression in tobacco, we proved that two regulatory complexes formed by a functional TT8 with different MYB(v-myb avian myeloblastosis viral oncogene homolog)-type partners significantly promoted expression of an anthocyanin biosynthetic gene and a proton pumping gene, leading to anthocyanin and citrate production. Our findings suggest that TT8, rather than dysfunctional Δ15-TT8, is possibly involved in modulating anthocyanin biosynthesis and its transport into vacuoles by proton gradients. However, increased mRNA levels of the dysfunctional alternative splicing transcript may act as a negative feedback to downregulate TT8 expression and limit anthocyanin accumulation in blood oranges.</p>","PeriodicalId":57479,"journal":{"name":"园艺研究(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10623405/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71489483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
'Vanilla' (XQC, brassica variety chinensis) is an important vegetable crop in the Brassica family, named for its strong volatile fragrance. In this study, we report the high-quality chromosome-level genome sequence of XQC. The assembled genome length was determined as 466.11 Mb, with an N50 scaffold of 46.20 Mb. A total of 59.50% repetitive sequences were detected in the XQC genome, including 47 570 genes. Among all examined Brassicaceae species, XQC had the closest relationship with B. rapa QGC ('QingGengCai') and B. rapa Pakchoi. Two whole-genome duplication (WGD) events and one recent whole-genome triplication (WGT) event occurred in the XQC genome in addition to an ancient WGT event. The recent WGT was observed to occur during 21.59-24.40 Mya (after evolution rate corrections). Our findings indicate that XQC experienced gene losses and chromosome rearrangements during the genome evolution of XQC. The results of the integrated genomic and transcriptomic analyses revealed critical genes involved in the terpenoid biosynthesis pathway and terpene synthase (TPS) family genes. In summary, we determined a chromosome-level genome of B. rapa XQC and identified the key candidate genes involved in volatile fragrance synthesis. This work can act as a basis for the comparative and functional genomic analysis and molecular breeding of B. rapa in the future.
{"title":"The high-quality sequencing of the <i>Brassica rapa</i> 'XiangQingCai' genome and exploration of genome evolution and genes related to volatile aroma.","authors":"Zhaokun Liu, Yanhong Fu, Huan Wang, Yanping Zhang, Jianjun Han, Yingying Wang, Shaoqin Shen, Chunjin Li, Mingmin Jiang, Xuemei Yang, Xiaoming Song","doi":"10.1093/hr/uhad187","DOIUrl":"https://doi.org/10.1093/hr/uhad187","url":null,"abstract":"<p><p>'Vanilla' (XQC, <i>brassica variety chinensis</i>) is an important vegetable crop in the Brassica family, named for its strong volatile fragrance. In this study, we report the high-quality chromosome-level genome sequence of XQC. The assembled genome length was determined as 466.11 Mb, with an N50 scaffold of 46.20 Mb. A total of 59.50% repetitive sequences were detected in the XQC genome, including 47 570 genes. Among all examined Brassicaceae species, XQC had the closest relationship with <i>B. rapa</i> QGC ('QingGengCai') and <i>B. rapa</i> Pakchoi. Two whole-genome duplication (WGD) events and one recent whole-genome triplication (WGT) event occurred in the XQC genome in addition to an ancient WGT event. The recent WGT was observed to occur during 21.59-24.40 Mya (after evolution rate corrections). Our findings indicate that XQC experienced gene losses and chromosome rearrangements during the genome evolution of XQC. The results of the integrated genomic and transcriptomic analyses revealed critical genes involved in the terpenoid biosynthesis pathway and terpene synthase (TPS) family genes. In summary, we determined a chromosome-level genome of <i>B. rapa</i> XQC and identified the key candidate genes involved in volatile fragrance synthesis. This work can act as a basis for the comparative and functional genomic analysis and molecular breeding of <i>B. rapa</i> in the future.</p>","PeriodicalId":57479,"journal":{"name":"园艺研究(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10611556/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71415488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chaenomeles speciosa (2n = 34), a medicinal and edible plant in the Rosaceae, is commonly used in traditional Chinese medicine. To date, the lack of genomic sequence and genetic studies has impeded efforts to improve its medicinal value. Herein, we report the use of an integrative approach involving PacBio HiFi (third-generation) sequencing and Hi-C scaffolding to assemble a high-quality telomere-to-telomere genome of C. speciosa. The genome comprised 650.4 Mb with a contig N50 of 35.5 Mb. Of these, 632.3 Mb were anchored to 17 pseudo-chromosomes, in which 12, 4, and 1 pseudo-chromosomes were represented by a single contig, two contigs, and four contigs, respectively. Eleven pseudo-chromosomes had telomere repeats at both ends, and four had telomere repeats at a single end. Repetitive sequences accounted for 49.5% of the genome, while a total of 45 515 protein-coding genes have been annotated. The genome size of C. speciosa was relatively similar to that of Malus domestica. Expanded or contracted gene families were identified and investigated for their association with different plant metabolisms or biological processes. In particular, functional annotation characterized gene families that were associated with the biosynthetic pathway of oleanolic and ursolic acids, two abundant pentacyclic triterpenoids in the fruits of C. speciosa. Taken together, this telomere-to-telomere and chromosome-level genome of C. speciosa not only provides a valuable resource to enhance understanding of the biosynthesis of medicinal compounds in tissues, but also promotes understanding of the evolution of the Rosaceae.
{"title":"A telomere-to-telomere reference genome provides genetic insight into the pentacyclic triterpenoid biosynthesis in <i>Chaenomeles speciosa</i>.","authors":"Shaofang He, Duanyang Weng, Yipeng Zhang, Qiusheng Kong, Keyue Wang, Naliang Jing, Fengfeng Li, Yuebin Ge, Hui Xiong, Lei Wu, De-Yu Xie, Shengqiu Feng, Xiaqing Yu, Xuekui Wang, Shaohua Shu, Zhinan Mei","doi":"10.1093/hr/uhad183","DOIUrl":"https://doi.org/10.1093/hr/uhad183","url":null,"abstract":"<p><p><i>Chaenomeles speciosa</i> (2<i>n</i> = 34), a medicinal and edible plant in the Rosaceae, is commonly used in traditional Chinese medicine. To date, the lack of genomic sequence and genetic studies has impeded efforts to improve its medicinal value. Herein, we report the use of an integrative approach involving PacBio HiFi (third-generation) sequencing and Hi-C scaffolding to assemble a high-quality telomere-to-telomere genome of <i>C. speciosa.</i> The genome comprised 650.4 Mb with a contig N50 of 35.5 Mb. Of these, 632.3 Mb were anchored to 17 pseudo-chromosomes, in which 12, 4, and 1 pseudo-chromosomes were represented by a single contig, two contigs, and four contigs, respectively. Eleven pseudo-chromosomes had telomere repeats at both ends, and four had telomere repeats at a single end. Repetitive sequences accounted for 49.5% of the genome, while a total of 45 515 protein-coding genes have been annotated. The genome size of <i>C. speciosa</i> was relatively similar to that of <i>Malus domestica</i>. Expanded or contracted gene families were identified and investigated for their association with different plant metabolisms or biological processes. In particular, functional annotation characterized gene families that were associated with the biosynthetic pathway of oleanolic and ursolic acids, two abundant pentacyclic triterpenoids in the fruits of <i>C. speciosa</i>. Taken together, this telomere-to-telomere and chromosome-level genome of <i>C. speciosa</i> not only provides a valuable resource to enhance understanding of the biosynthesis of medicinal compounds in tissues, but also promotes understanding of the evolution of the Rosaceae.</p>","PeriodicalId":57479,"journal":{"name":"园艺研究(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10623406/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71489484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Geraniol is an important contributor to the pleasant floral scent of tea products and one of the most abundant aroma compounds in tea plants; however, its biosynthesis and physiological function in response to stress in tea plants remain unclear. The proteins encoded by the full-length terpene synthase (CsTPS1) and its alternative splicing isoform (CsTPS1-AS) could catalyze the formation of geraniol when GPP was used as a substrate in vitro, whereas the expression of CsTPS1-AS was only significantly induced by Colletotrichum gloeosporioides and Neopestalotiopsis sp. infection. Silencing of CsTPS1 and CsTPS1-AS resulted in a significant decrease of geraniol content in tea plants. The geraniol content and disease resistance of tea plants were compared when CsTPS1 and CsTPS1-AS were silenced. Down-regulation of the expression of CsTPS1-AS reduced the accumulation of geraniol, and the silenced tea plants exhibited greater susceptibility to pathogen infection than control plants. However, there was no significant difference observed in the geraniol content and pathogen resistance between CsTPS1-silenced plants and control plants in the tea plants infected with two pathogens. Further analysis showed that silencing of CsTPS1-AS led to a decrease in the expression of the defense-related genes PR1 and PR2 and SA pathway-related genes in tea plants, which increased the susceptibility of tea plants to pathogens infections. Both in vitro and in vivo results indicated that CsTPS1 is involved in the regulation of geraniol formation and plant defense via alternative splicing in tea plants. The results of this study provide new insights into geraniol biosynthesis and highlight the role of monoterpene synthases in modulating plant disease resistance via alternative splicing.
{"title":"A geraniol synthase regulates plant defense via alternative splicing in tea plants.","authors":"Hao Jiang, Mengting Zhang, Feng Yu, Xuehui Li, Jieyang Jin, Youjia Zhou, Qiang Wang, Tingting Jing, Xiaochun Wan, Wilfried Schwab, Chuankui Song","doi":"10.1093/hr/uhad184","DOIUrl":"10.1093/hr/uhad184","url":null,"abstract":"<p><p>Geraniol is an important contributor to the pleasant floral scent of tea products and one of the most abundant aroma compounds in tea plants; however, its biosynthesis and physiological function in response to stress in tea plants remain unclear. The proteins encoded by the full-length terpene synthase (<i>CsTPS1</i>) and its alternative splicing isoform (<i>CsTPS1</i>-<i>AS</i>) could catalyze the formation of geraniol when GPP was used as a substrate <i>in vitro</i>, whereas the expression of <i>CsTPS1</i>-<i>AS</i> was only significantly induced by <i>Colletotrichum gloeosporioides</i> and <i>Neopestalotiopsis</i> sp. infection. Silencing of <i>CsTPS1</i> and <i>CsTPS1</i>-<i>AS</i> resulted in a significant decrease of geraniol content in tea plants. The geraniol content and disease resistance of tea plants were compared when <i>CsTPS1</i> and <i>CsTPS1</i>-<i>AS</i> were silenced. Down-regulation of the expression of <i>CsTPS1</i>-<i>AS</i> reduced the accumulation of geraniol, and the silenced tea plants exhibited greater susceptibility to pathogen infection than control plants. However, there was no significant difference observed in the geraniol content and pathogen resistance between <i>CsTPS1</i>-silenced plants and control plants in the tea plants infected with two pathogens. Further analysis showed that silencing of <i>CsTPS1</i>-<i>AS</i> led to a decrease in the expression of the defense-related genes <i>PR1</i> and <i>PR2</i> and SA pathway-related genes in tea plants, which increased the susceptibility of tea plants to pathogens infections<i>.</i> Both <i>in vitro</i> and <i>in vivo</i> results indicated that <i>CsTPS1</i> is involved in the regulation of geraniol formation and plant defense via alternative splicing in tea plants. The results of this study provide new insights into geraniol biosynthesis and highlight the role of monoterpene synthases in modulating plant disease resistance via alternative splicing.</p>","PeriodicalId":57479,"journal":{"name":"园艺研究(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10599320/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54232452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-07eCollection Date: 2023-10-01DOI: 10.1093/hr/uhad185
Qian Li, Guang Wang, Ling Zhang, Shijiang Zhu
Internal browning (IB), a major physiological disorder of pineapples, usually happens in postharvest processes, but the underlying mechanism remains elusive. The bHLH transcription factors are involved in regulating various biological processes, but whether they could regulate tissue browning in fruit during storage remains unknown. Here we showed that the phenolic biosynthesis pathway was activated in pineapples showing IB following 9 days of storage. AcbHLH144 expression was the highest of the 180 transcription factors identified, downregulated in pineapple with IB, and negatively correlated with the major phenolic biosynthetic genes. AcbHLH144 was shown to be localized in the nucleus and its transient overexpression in pineapples and overexpression in Arabidopsis decreased phenolic biosynthesis. The yeast one-hybrid assay and electrophoretic mobility shift assay showed that AcbHLH144 directly bound to the Ac4CL5 promoter and the dual-luciferase reporter assay showed that it inactivated Ac4CL5 transcription. These results strongly suggest AcbHLH144 as a repressor for phenolic biosynthesis. Abscisic acid (ABA) alleviated IB, reduced phenolic accumulation, and downregulated phenolic biosynthetic genes, including Ac4CL5. Transcriptomic analysis showed that AcbHLH144 was the most upregulated of all 39 bHLHs in response to ABA. ABA enhanced AcbHLH144 expression, reduced phenolic contents, and downregulated phenolic biosynthetic genes in pineapples transiently overexpressing AcbHLH144. Moreover, ABA enhanced enzyme activity of GUS driven by the AcbHLH144 promoter. These results showed that AcbHLH144 as a repressor for phenolic biosynthesis could be activated by ABA. Collectively, the work demonstrated that AcbHLH144 negatively regulated phenolic biosynthesis via inactivating Ac4CL5 transcription to modulate pineapple IB. The findings provide novel insight into the role of AcbHLH144 in modulating pineapple IB during postharvest processes.
{"title":"AcbHLH144 transcription factor negatively regulates phenolic biosynthesis to modulate pineapple internal browning.","authors":"Qian Li, Guang Wang, Ling Zhang, Shijiang Zhu","doi":"10.1093/hr/uhad185","DOIUrl":"https://doi.org/10.1093/hr/uhad185","url":null,"abstract":"<p><p>Internal browning (IB), a major physiological disorder of pineapples, usually happens in postharvest processes, but the underlying mechanism remains elusive. The bHLH transcription factors are involved in regulating various biological processes, but whether they could regulate tissue browning in fruit during storage remains unknown. Here we showed that the phenolic biosynthesis pathway was activated in pineapples showing IB following 9 days of storage. <i>AcbHLH144</i> expression was the highest of the 180 transcription factors identified, downregulated in pineapple with IB, and negatively correlated with the major phenolic biosynthetic genes. AcbHLH144 was shown to be localized in the nucleus and its transient overexpression in pineapples and overexpression in <i>Arabidopsis</i> decreased phenolic biosynthesis. The yeast one-hybrid assay and electrophoretic mobility shift assay showed that AcbHLH144 directly bound to the <i>Ac4CL5</i> promoter and the dual-luciferase reporter assay showed that it inactivated <i>Ac4CL5</i> transcription. These results strongly suggest AcbHLH144 as a repressor for phenolic biosynthesis. Abscisic acid (ABA) alleviated IB, reduced phenolic accumulation, and downregulated phenolic biosynthetic genes, including <i>Ac4CL5</i>. Transcriptomic analysis showed that <i>AcbHLH144</i> was the most upregulated of all 39 bHLHs in response to ABA. ABA enhanced <i>AcbHLH144</i> expression, reduced phenolic contents, and downregulated phenolic biosynthetic genes in pineapples transiently overexpressing <i>AcbHLH144.</i> Moreover, ABA enhanced enzyme activity of GUS driven by the <i>AcbHLH144</i> promoter. These results showed that AcbHLH144 as a repressor for phenolic biosynthesis could be activated by ABA. Collectively, the work demonstrated that AcbHLH144 negatively regulated phenolic biosynthesis via inactivating <i>Ac4CL5</i> transcription to modulate pineapple IB. The findings provide novel insight into the role of AcbHLH144 in modulating pineapple IB during postharvest processes.</p>","PeriodicalId":57479,"journal":{"name":"园艺研究(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10611554/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71415485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eggplant (Solanum melongena L.) is a highly nutritious vegetable. Here, the molecular mechanism of color formation in eggplants was determined using six eggplant cultivars with different peel colors and two SmMYB113-overexpressing transgenic eggplants with a purple peel and pulp. Significant differentially expressed genes (DEGs) were identified by RNA-sequencing analysis using the following criteria: log2(sample1/sample2) ≥ 0.75 and q-value ≤ 0.05. Two analytical strategies were used to identify genes related to the different peel color according to the peel color, flavonoids content, delphinidins/flavonoids ratio, and the content of anthocyanins. Finally, 27 novel genes were identified to be related to the color difference among eggplant peels and 32 novel genes were identified to be related to anthocyanin biosynthesis and regulated by SmMYB113. Venn analysis revealed that SmCytb5, SmGST, SmMATE, SmASAT3, and SmF3'5'M were shared among both sets of novel genes. Transient expression assay in tobacco suggested that these five genes were not sufficient for inducing anthocyanin biosynthesis alone, but they play important roles in anthocyanin accumulation in eggplant peels. Yeast one-hybrid, electrophoretic mobility shift assay and dual-luciferase assays indicated that the expression of the five genes could be directly activated by SmMYB113 protein. Finally, a regulatory model for the mechanism of color formation in eggplant was proposed. Overall, the results of this study provide useful information that enhances our understanding of the molecular mechanism underlying the different color formation in eggplant.
{"title":"RNA-sequencing analysis reveals novel genes involved in the different peel color formation in eggplant.","authors":"Jing Li, Senlin Jiang, Guobin Yang, Yanwei Xu, Lujun Li, Fengjuan Yang","doi":"10.1093/hr/uhad181","DOIUrl":"10.1093/hr/uhad181","url":null,"abstract":"<p><p>Eggplant (<i>Solanum melongena</i> L.) is a highly nutritious vegetable. Here, the molecular mechanism of color formation in eggplants was determined using six eggplant cultivars with different peel colors and two <i>SmMYB113</i>-overexpressing transgenic eggplants with a purple peel and pulp. Significant differentially expressed genes (DEGs) were identified by RNA-sequencing analysis using the following criteria: log<sub>2</sub><sup>(sample1/sample2)</sup> ≥ 0.75 and q-value ≤ 0.05. Two analytical strategies were used to identify genes related to the different peel color according to the peel color, flavonoids content, delphinidins/flavonoids ratio, and the content of anthocyanins. Finally, 27 novel genes were identified to be related to the color difference among eggplant peels and 32 novel genes were identified to be related to anthocyanin biosynthesis and regulated by SmMYB113. Venn analysis revealed that <i>SmCytb5</i>, <i>SmGST</i>, <i>SmMATE</i>, <i>SmASAT3</i>, and <i>SmF3'5'M</i> were shared among both sets of novel genes. Transient expression assay in tobacco suggested that these five genes were not sufficient for inducing anthocyanin biosynthesis alone, but they play important roles in anthocyanin accumulation in eggplant peels. Yeast one-hybrid, electrophoretic mobility shift assay and dual-luciferase assays indicated that the expression of the five genes could be directly activated by SmMYB113 protein. Finally, a regulatory model for the mechanism of color formation in eggplant was proposed. Overall, the results of this study provide useful information that enhances our understanding of the molecular mechanism underlying the different color formation in eggplant.</p>","PeriodicalId":57479,"journal":{"name":"园艺研究(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10599318/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"54232454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Recognized as a pivotal developmental transition, flowering marks the continuation of a plant's life cycle. Vernalization and photoperiod are two major flowering pathways orchestrating numerous florigenic signals. Methylation, including histone, DNA and RNA methylation, is one of the recent foci in plant development. Considerable studies reveal that methylation seems to show an increasing potential regulatory role in plant flowering via altering relevant gene expression without altering the genetic basis. However, little has been reviewed about whether and how methylation acts on vernalization- and photoperiod-induced flowering before and after FLOWERING LOCUS C (FLC) reactivation, what role RNA methylation plays in vernalization- and photoperiod-induced flowering, how methylation participates simultaneously in both vernalization- and photoperiod-induced flowering, the heritability of methylation memory under the vernalization/photoperiod pathway, and whether and how methylation replaces vernalization/photoinduction to regulate flowering. Our review provides insight about the crosstalk among the genetic control of the flowering gene network, methylation (methyltransferases/demethylases) and external signals (cold, light, sRNA and phytohormones) in vernalization and photoperiod pathways. The existing evidence that RNA methylation may play a potential regulatory role in vernalization- and photoperiod-induced flowering has been gathered and represented for the first time. This review speculates about and discusses the possibility of substituting methylation for vernalization and photoinduction to promote flowering. Current evidence is utilized to discuss the possibility of future methylation reagents becoming flowering regulators at the molecular level.
{"title":"Role of methylation in vernalization and photoperiod pathway: a potential flowering regulator?","authors":"Meimei Shi, Chunlei Wang, Peng Wang, Fahong Yun, Zhiya Liu, Fujin Ye, Lijuan Wei, Weibiao Liao","doi":"10.1093/hr/uhad174","DOIUrl":"10.1093/hr/uhad174","url":null,"abstract":"<p><p>Recognized as a pivotal developmental transition, flowering marks the continuation of a plant's life cycle. Vernalization and photoperiod are two major flowering pathways orchestrating numerous florigenic signals. Methylation, including histone, DNA and RNA methylation, is one of the recent foci in plant development. Considerable studies reveal that methylation seems to show an increasing potential regulatory role in plant flowering via altering relevant gene expression without altering the genetic basis. However, little has been reviewed about whether and how methylation acts on vernalization- and photoperiod-induced flowering before and after <i><i>FLOWERING LOCUS C</i> (<i>FLC</i>)</i> reactivation, what role RNA methylation plays in vernalization- and photoperiod-induced flowering, how methylation participates simultaneously in both vernalization- and photoperiod-induced flowering, the heritability of methylation memory under the vernalization/photoperiod pathway, and whether and how methylation replaces vernalization/photoinduction to regulate flowering. Our review provides insight about the crosstalk among the genetic control of the flowering gene network, methylation (methyltransferases/demethylases) and external signals (cold, light, sRNA and phytohormones) in vernalization and photoperiod pathways. The existing evidence that RNA methylation may play a potential regulatory role in vernalization- and photoperiod-induced flowering has been gathered and represented for the first time. This review speculates about and discusses the possibility of substituting methylation for vernalization and photoinduction to promote flowering. Current evidence is utilized to discuss the possibility of future methylation reagents becoming flowering regulators at the molecular level.</p>","PeriodicalId":57479,"journal":{"name":"园艺研究(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10569243/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41241309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-29eCollection Date: 2023-10-01DOI: 10.1093/hr/uhad172
Zhen Zhang, Changyue Jiang, Cui Chen, Kai Su, Hong Lin, Yuhui Zhao, Yinshan Guo
Grape white rot is a disease caused by Coniella diplodiella (Speg.) Sacc. (Cd) can drastically reduce the production and quality of grape (Vitis vinifera). WRKY transcription factors play a vital role in the regulation of plant resistance to pathogens, but their functions in grape white rot need to be further explored. Here, we found that the expression of the WRKY IIe subfamily member VvWRKY5 was highly induced by Cd infection and jasmonic acid (JA) treatment. Transient injection and stable overexpression (in grape calli and Arabidopsis) demonstrated that VvWRKY5 positively regulated grape resistance to white rot. We also determined that VvWRKY5 regulated the JA response by directly binding to the promoters of VvJAZ2 (a JA signaling suppressor) and VvMYC2 (a JA signaling activator), thereby inhibiting and activating the transcription of VvJAZ2 and VvMYC2, respectively. Furthermore, the interaction between VvJAZ2 and VvWRKY5 enhanced the suppression and promotion of VvJAZ2 and VvMYC2 activities by VvWRKY5, respectively. When VvWRKY5 was overexpressed in grape, JA content was also increased. Overall, our results suggested that VvWRKY5 played a key role in regulating JA biosynthesis and signal transduction as well as enhancing white rot resistance in grape. Our results also provide theoretical guidance for the development of elite grape cultivars with enhanced pathogen resistance.
{"title":"VvWRKY5 enhances white rot resistance in grape by promoting the jasmonic acid pathway.","authors":"Zhen Zhang, Changyue Jiang, Cui Chen, Kai Su, Hong Lin, Yuhui Zhao, Yinshan Guo","doi":"10.1093/hr/uhad172","DOIUrl":"10.1093/hr/uhad172","url":null,"abstract":"<p><p>Grape white rot is a disease caused by <i>Coniella diplodiella</i> (Speg.) Sacc. (<i>Cd</i>) can drastically reduce the production and quality of grape (<i>Vitis vinifera</i>). WRKY transcription factors play a vital role in the regulation of plant resistance to pathogens, but their functions in grape white rot need to be further explored. Here, we found that the expression of the WRKY IIe subfamily member <i>VvWRKY5</i> was highly induced by <i>Cd</i> infection and jasmonic acid (JA) treatment. Transient injection and stable overexpression (in grape calli and <i>Arabidopsis</i>) demonstrated that VvWRKY5 positively regulated grape resistance to white rot. We also determined that VvWRKY5 regulated the JA response by directly binding to the promoters of <i>VvJAZ2</i> (a JA signaling suppressor) and <i>VvMYC2</i> (a JA signaling activator), thereby inhibiting and activating the transcription of <i>VvJAZ2</i> and <i>VvMYC2</i>, respectively. Furthermore, the interaction between VvJAZ2 and VvWRKY5 enhanced the suppression and promotion of <i>VvJAZ2</i> and <i>VvMYC2</i> activities by VvWRKY5, respectively. When <i>VvWRKY5</i> was overexpressed in grape, JA content was also increased. Overall, our results suggested that VvWRKY5 played a key role in regulating JA biosynthesis and signal transduction as well as enhancing white rot resistance in grape. Our results also provide theoretical guidance for the development of elite grape cultivars with enhanced pathogen resistance.</p>","PeriodicalId":57479,"journal":{"name":"园艺研究(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10569242/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41241311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}