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Li X, Zheng Y, Luo L, Chen Q, Yang T, Yang Y, Qiao Q, Kong X, Yang Y. The evolution and functional divergence of FT-related genes in controlling flowering time in Brassica rapa ssp. rapa. PLANT CELL REPORTS 2024; 43:86. [PMID: 38453734 PMCID: PMC10920429 DOI: 10.1007/s00299-024-03166-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 01/26/2024] [Indexed: 03/09/2024]
Abstract
KEY MESSAGE The BrrFT paralogues exhibit distinct expression patterns and play different roles in regulating flowering time, and BrrFT4 competes with BrrFT1 and BrrFT2 to interact with BrrFD proteins. Flowering time is an important agricultural trait for Brassica crops, and early bolting strongly affects the yield and quality of Brassica rapa ssp. rapa. Flowering Locus T paralogues play an important role in regulating flowering time. In this study, we identified FT-related genes in turnip by phylogenetic classification, and four BrrFT homoeologs that shared with high identities with BraFT genes were isolated. The different gene structures, promoter binding sites, and expression patterns observed indicated that these genes may play different roles in flowering time regulation. Further genetic and biochemical experiments showed that as for FT-like paralogues, BrrFT2 acted as the key floral inducer, and BrrFT1 seems to act as a mild 'florigen' protein. However, BrrFT4 acts as a floral repressor and antagonistically regulates flowering time by competing with BrrFT1 and BrrFT2 to bind BrrFD proteins. BrrFT3 may have experienced loss of function via base shift mutation. Our results revealed the potential roles of FT-related genes in flowering time regulation in turnip.
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Affiliation(s)
- Xieshengyang Li
- School of Agriculture, Yunnan University, Kunming, 650091, Yunnan, China
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China
| | - Yan Zheng
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China
| | - Landi Luo
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China
| | - Qian Chen
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China
| | - Tianyu Yang
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China
| | - Ya Yang
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China
| | - Qin Qiao
- College of Horticulture and Landscape, Yunnan Agricultural University, Kunming, 650201, Yunnan, China.
| | - Xiangxiang Kong
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China.
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China.
| | - Yongping Yang
- Germplasm Bank of Wild Species, Yunnan Key Laboratory for Crop Wild Relatives Omics, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China.
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, Yunnan, China.
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Ahn JY, Subburaj S, Yan F, Yao J, Chandrasekaran A, Ahn KG, Lee GJ. Molecular Evaluation of the Effects of FLC Homologs and Coordinating Regulators on the Flowering Responses to Vernalization in Cabbage ( Brassica oleracea var. capitata) Genotypes. Genes (Basel) 2024; 15:154. [PMID: 38397144 PMCID: PMC10887945 DOI: 10.3390/genes15020154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 01/08/2024] [Accepted: 01/20/2024] [Indexed: 02/25/2024] Open
Abstract
The flowering loci of cabbage must be understood to boost their productivity. In this study, to clarify the flowering mechanisms of cabbage, we examined the three flowering repressors BoFLC1, 2 and 3, and the flowering regulators BoGI, BoCOOLAIR, and BoVIN3 of early (CAB1), middle (CAB3), and late (CAB5) flowering cabbage genotypes. Analysis of allele-specifically amplified genomic DNA and various sequence alignments demonstrated that maximal insertions and deletions influenced cabbage flowering behavior, notably in CAB3 and CAB5. Phylogenetic studies showed that BoFLC1, 2, and 3 in the CAB1, 3, and 5 genotypes had the highest homologies to other Brassica species, with CAB3 and 5 the most similar. Although CAB3 and CAB5 have comparable genetic patterns, flowering repressors and flowering regulators were investigated individually with and without vernalization to determine their minor flowering differences. The expression investigation revealed that vernalized CAB5 downregulated all BoFLC genes compared to CAB3 and, in contrast, CAB3 exhibited upregulated BoCOOLAIR. We hypothesized that the CAB3 BoFLC locus' additional insertions may have led to BoCOOLAIR overexpression and BoFLC downregulation. This study sheds light on cabbage genotypes-particularly those of CAB1 and CAB5-and suggests that structural variations in BoFLC2 and 3 bind flowering regulators, such as COOLAIR, which may affect cabbage flowering time.
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Affiliation(s)
- Ju-Young Ahn
- Department of Horticulture, Chungnam National University, Daejeon 34134, Republic of Korea; (J.-Y.A.); (S.S.); (A.C.)
| | - Saminathan Subburaj
- Department of Horticulture, Chungnam National University, Daejeon 34134, Republic of Korea; (J.-Y.A.); (S.S.); (A.C.)
| | - Fanzhuang Yan
- Department of Smart Agriculture Systems, Chungnam National University, Daejeon 34134, Republic of Korea; (F.Y.); (J.Y.)
| | - Jian Yao
- Department of Smart Agriculture Systems, Chungnam National University, Daejeon 34134, Republic of Korea; (F.Y.); (J.Y.)
| | - Ajithan Chandrasekaran
- Department of Horticulture, Chungnam National University, Daejeon 34134, Republic of Korea; (J.-Y.A.); (S.S.); (A.C.)
- Department of Smart Agriculture Systems, Chungnam National University, Daejeon 34134, Republic of Korea; (F.Y.); (J.Y.)
| | - Kyoung-Gu Ahn
- Joen Seed Co., Ltd., Goesan 28051, Republic of Korea;
| | - Geung-Joo Lee
- Department of Horticulture, Chungnam National University, Daejeon 34134, Republic of Korea; (J.-Y.A.); (S.S.); (A.C.)
- Department of Smart Agriculture Systems, Chungnam National University, Daejeon 34134, Republic of Korea; (F.Y.); (J.Y.)
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Yin X, Yang D, Zhao Y, Yang X, Zhou Z, Sun X, Kong X, Li X, Wang G, Duan Y, Yang Y, Yang Y. Differences in pseudogene evolution contributed to the contrasting flavors of turnip and Chiifu, two Brassica rapa subspecies. PLANT COMMUNICATIONS 2023; 4:100427. [PMID: 36056558 PMCID: PMC9860189 DOI: 10.1016/j.xplc.2022.100427] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 07/30/2022] [Accepted: 08/29/2022] [Indexed: 06/15/2023]
Abstract
Pseudogenes are important resources for investigation of genome evolution and genomic diversity because they are nonfunctional but have regulatory effects that influence plant adaptation and diversification. However, few systematic comparative analyses of pseudogenes in closely related species have been conducted. Here, we present a turnip (Brassica rapa ssp. rapa) genome sequence and characterize pseudogenes among diploid Brassica species/subspecies. The results revealed that the number of pseudogenes was greatest in Brassica oleracea (CC genome), followed by B. rapa (AA genome) and then Brassica nigra (BB genome), implying that pseudogene differences emerged after species differentiation. In Brassica AA genomes, pseudogenes were distributed asymmetrically on chromosomes because of numerous chromosomal insertions/rearrangements, which contributed to the diversity among subspecies. Pseudogene differences among subspecies were reflected in the flavor-related glucosinolate (GSL) pathway. Specifically, turnip had the highest content of pungent substances, probably because of expansion of the methylthioalkylmalate synthase-encoding gene family in turnips; these genes were converted into pseudogenes in B. rapa ssp. pekinensis (Chiifu). RNA interference-based silencing of the gene encoding 2-oxoglutarate-dependent dioxygenase 2, which is also associated with flavor and anticancer substances in the GSL pathway, resulted in increased abundance of anticancer compounds and decreased pungency of turnip and Chiifu. These findings revealed that pseudogene differences between turnip and Chiifu influenced the evolution of flavor-associated GSL metabolism-related genes, ultimately resulting in the different flavors of turnip and Chiifu.
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Affiliation(s)
- Xin Yin
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| | - Danni Yang
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Youjie Zhao
- College of Big Data and Intelligent Engineering, Southwest Forestry University, Kunming, Yunnan, China
| | - Xingyu Yang
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhili Zhou
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| | - Xudong Sun
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| | - Xiangxiang Kong
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| | - Xiong Li
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| | - Guangyan Wang
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| | - Yuanwen Duan
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| | - Yunqiang Yang
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
| | - Yongping Yang
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China; Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
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Whole-transcriptome sequencing reveals a vernalization-related ceRNA regulatory network in chinese cabbage (Brassica campestris L. ssp. pekinensis). BMC Genomics 2021; 22:819. [PMID: 34773977 PMCID: PMC8590779 DOI: 10.1186/s12864-021-08110-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 10/18/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The transition from vegetative growth to reproductive growth involves various pathways. Vernalization is a crucial process for floral organ formation and regulation of flowering time that is widely utilized in plant breeding. In this study, we aimed to identify the global landscape of mRNAs, microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) related to vernalization in Chinese cabbage. These data were then used to construct a competitive endogenous RNA (ceRNA) network that provides valuable information to better understand the vernalization response. RESULTS In this study, seeds sampled from the Chinese cabbage doubled haploid (DH) line 'FT' with or without vernalization treatment were used for whole-transcriptome sequencing. A total of 2702 differentially expressed (DE) mRNAs, 151 DE lncRNAs, 16 DE circRNAs, and 233 DE miRNAs were identified in the vernalization-treated seeds. Various transcription factors, such as WRKY, MYB, NAC, bHLH, MADS-box, zinc finger protein CONSTANS-like gene, and B3 domain protein, and regulatory proteins that play important roles in the vernalization pathway were identified. Additionally, we constructed a vernalization-related ceRNA-miRNA-target gene network and obtained 199 pairs of ceRNA relationships, including 108 DEmiRNA‒DEmRNA, 67 DEmiRNA‒DElncRNA, and 12 DEmiRNA‒DEcircRNA interactions, in Chinese cabbage. Furthermore, several important vernalization-related genes and their interacting lncRNAs, circRNAs, and miRNAs, which are involved in the regulation of flowering time, floral organ formation, bolting, and flowering, were identified. CONCLUSIONS Our results reveal the potential mRNA and non-coding RNAs involved in vernalization, providing a foundation for further studies on the molecular mechanisms underlying vernalization in Chinese cabbage.
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Lehretz GG, Sonnewald S, Sonnewald U. Assimilate highway to sink organs - Physiological consequences of SP6A overexpression in transgenic potato (Solanum tuberosum L.). JOURNAL OF PLANT PHYSIOLOGY 2021; 266:153530. [PMID: 34610522 DOI: 10.1016/j.jplph.2021.153530] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 09/19/2021] [Indexed: 06/13/2023]
Abstract
Leaf/stem-specific overexpression of SP6A, the FLOWERING LOCUS T homolog in potato (Solanum tuberosum), was previously shown to induce tuberization leading to higher tuber numbers and yield under ambient and abiotic stress conditions. In this study, we investigated the mechanism underlying SP6A action. Overexpression of SP6A reduced shoot growth, mainly by inhibition of stem elongation and secondary growth, and by repression of apical bud outgrowth. In contrast, root growth and lateral shoot emergence from basal nodes was promoted. Tracer experiments using the fluorescent sucrose analogue esculin revealed that stems of SP6A overexpressing plants transport assimilates more efficiently to belowground sinks, e.g. roots and tubers, compared to wild-type plants. This was accompanied by a lower level of sucrose leakage from the transport phloem into neighboring parenchyma cells and the inhibition of flower formation. We demonstrate the ability of SP6A to control assimilate allocation to belowground sinks and postulate that selection of beneficial SP6A alleles will enable potato breeding to alter plant architecture and to increase tuber yield under conditions of expected climate change.
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Affiliation(s)
- Günter G Lehretz
- Department of Biology, Division of Biochemistry, Friedrich-Alexander-University Erlangen-Nuremberg, Staudtstrasse 5, 91058, Erlangen, Germany
| | - Sophia Sonnewald
- Department of Biology, Division of Biochemistry, Friedrich-Alexander-University Erlangen-Nuremberg, Staudtstrasse 5, 91058, Erlangen, Germany
| | - Uwe Sonnewald
- Department of Biology, Division of Biochemistry, Friedrich-Alexander-University Erlangen-Nuremberg, Staudtstrasse 5, 91058, Erlangen, Germany.
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Han Q, Sakaguchi S, Wakabayashi T, Setoguchi H. Association between RsFT, RsFLC and RsCOL5 ( A&B) expression and flowering regulation in Japanese wild radish. AOB PLANTS 2021; 13:plab039. [PMID: 34285794 PMCID: PMC8286712 DOI: 10.1093/aobpla/plab039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 06/19/2021] [Indexed: 04/14/2023]
Abstract
Flowering is an important step in the life cycle of plants and indicates adaptability to external climatic cues such as temperature and photoperiod. We investigated the expression patterns of core genes related to flowering-time regulation in Japanese wild radish (Raphanus sativus var. raphanistroides) with different vernalization requirements (obligate and facultative) and further identified climatic cues that may act as natural selective forces. Specifically, we analysed flowering-time variation under different cold and photoperiod treatments in Japanese wild radish collected from the Hokkaido (northern lineage) and Okinawa (southern lineage) islands, which experience contrasting climatic cues. The cultivation experiment verified the obligate and facultative vernalization requirements of the northern and southern wild radish accessions, respectively. The expression of major genes involved in flowering time indicated that RsFLC and RsCOL5 (A&B) may interact to regulate flowering time. Notably, floral initiation in the northern lineage was strongly correlated with RsFLC expression, whereas flowering in the southern linage was correlated with induction of RsCOL5-A expression, despite high RsFLC transcript levels. These results suggested that the northern accessions are more sensitive to prolonged cold exposure, whereas the southern accessions are more sensitive to photoperiod. These different mechanisms ultimately confer an optimal flowering time in natural populations in response to locally contrasting climatic cues. This study provides new insights into the variant mechanisms underlying floral pathways in Japanese wild radish from different geographic locations.
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Affiliation(s)
- Qingxiang Han
- College of Life Sciences, Zaozhuang University, Zaozhuang City, Shandong Province, 277160, China
- Corresponding author e-mail address:
| | - Shota Sakaguchi
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, 606-8501, Japan
| | - Tomomi Wakabayashi
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, 606-8501, Japan
| | - Hiroaki Setoguchi
- Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, 606-8501, Japan
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Zheng Y, Gao Z, Luo L, Wang Y, Chen Q, Yang Y, Kong X, Yang Y. Divergence of the genetic contribution of FRIGIDA homologues in regulating the flowering time in Brassica rapa ssp. rapa. Gene 2021; 796-797:145790. [PMID: 34175395 DOI: 10.1016/j.gene.2021.145790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 06/04/2021] [Accepted: 06/22/2021] [Indexed: 10/21/2022]
Affiliation(s)
- Yan Zheng
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zean Gao
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Landi Luo
- School of Ecology and Environmental Science, Yunnan University, Kunming 650504, China
| | - Yonggang Wang
- Agricultural Technology Extension Center of Zhaoyang District, Zhaotong 657000, China
| | - Qian Chen
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| | - Ya Yang
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| | - Xiangxiang Kong
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
| | - Yongping Yang
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
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Hong L, Niu F, Lin Y, Wang S, Chen L, Jiang L. MYB106 is a negative regulator and a substrate for CRL3 BPM E3 ligase in regulating flowering time in Arabidopsis thaliana. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:1104-1119. [PMID: 33470537 DOI: 10.1111/jipb.13071] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Accepted: 01/16/2021] [Indexed: 05/18/2023]
Abstract
Flowering time is crucial for successful reproduction in plants, the onset and progression of which are strictly controlled. However, flowering time is a complex and environmentally responsive history trait and the underlying mechanisms still need to be fully characterized. Post-translational regulation of the activities of transcription factors (TFs) is a dynamic and essential mechanism for plant growth and development. CRL3BPM E3 ligase is a CULLIN3-based E3 ligase involved in orchestrating protein stability via the ubiquitin proteasome pathway. Our study shows that the mutation of MYB106 induced early flowering phenotype while over-expression of MYB106 delayed Arabidopsis flowering. Transcriptome analysis of myb106 mutants reveals 257 differentially expressed genes between wild type and myb106-1 mutants, including Flowering Locus T (FT) which is related to flowering time. Moreover, in vitro electrophoretic mobility shift assays (EMSA), in vivo chromatin immunoprecipitation quantitative polymerase chain reaction (ChIP-qPCR) assays and dual luciferase assays demonstrate that MYB106 directly binds to the promoter of FT to suppress its expression. Furthermore, we confirm that MYB106 interacts with BPM proteins which are further identified by CRL3BPM E3 ligases as the substrate. Taken together, we have identified MYB106 as a negative regulator in the control of flowering time and a new substrate for CRL3BPM E3 ligases in Arabidopsis.
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Affiliation(s)
- Liu Hong
- Center for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Fangfang Niu
- Center for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Youshun Lin
- Center for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Shuang Wang
- Center for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- Shenzhen Technology University, Shenzhen, 518000, China
| | - Liyuan Chen
- Center for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- School of Chemical Biology & Biotechnology, Peking University Shenzhen Graduate School, Nanshan District, Shenzhen, 518055, China
| | - Liwen Jiang
- Center for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, 518057, China
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Hong L, Niu F, Lin Y, Wang S, Chen L, Jiang L. MYB117 is a negative regulator of flowering time in Arabidopsis. PLANT SIGNALING & BEHAVIOR 2021; 16:1901448. [PMID: 33779489 PMCID: PMC8078523 DOI: 10.1080/15592324.2021.1901448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Plant flowering is crucial for the onset and progression of reproduction processes. The control of flowering time is a sophisticated system with multiple known regulatory mechanisms in plants. Here, we show that MYB117 participates in the flowering time regulation in Arabidopsis as myb117 mutants exhibited early flowering phenotypes under long-day condition. Transcriptome analysis of myb117 mutants revealed 410 differentially expressed genes between wild type and myb117-1 mutants, where selective genes including the Flowering Locus T (FT) were further confirmed by qRT-PCR analysis. Further, in vivo dual-luciferase and chromatin immunoprecipitation quantitative PCR (ChIP-qPCR) assays showed that MYB117 directly binds to the promoter of FT to suppress its expression. Taken together, we have revealed the transcriptome profile of myb117 mutants and identified MYB117 as a negative regulator in controlling flowering time through regulating the expression of FT in Arabidopsis.
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Affiliation(s)
- Liu Hong
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Fangfang Niu
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- CONTACT Fangfang Niu
| | - Youshun Lin
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Shuang Wang
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- College of Health Science and Environmental Engineering, Shenzhen Technology University, Shenzhen, 518000, China
| | - Liyuan Chen
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- School of Chemical Biology & Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, Nanshan District, 518055, China
- Liyuan Chen Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Liwen Jiang
- Centre for Cell & Developmental Biology, State Key Laboratory of Agrobiotechnology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- Institute of Plant Molecular Biology and Agricultural Biotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, 518057, China
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10
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Yin X, Yang Y, Lv Y, Li Y, Yang D, Yue Y, Yang Y. BrrICE1.1 is associated with putrescine synthesis through regulation of the arginine decarboxylase gene in freezing tolerance of turnip (Brassica rapa var. rapa). BMC PLANT BIOLOGY 2020; 20:504. [PMID: 33148172 PMCID: PMC7641815 DOI: 10.1186/s12870-020-02697-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 10/12/2020] [Indexed: 06/02/2023]
Abstract
BACKGROUND In the agricultural areas of Qinghai-Tibet Plateau, temperature varies widely from day to night during the growing season, which makes the extreme temperature become one of the limiting factors of crop yield. Turnip (Brassica rapa var. rapa) is a traditional crop of Tibet grown in the Tibet Plateau, but its molecular and metabolic mechanisms of freezing tolerance are unclear. RESULTS Here, based on the changes in transcriptional and metabolic levels of Tibetan turnip under freezing treatment, the expression of the arginine decarboxylase gene BrrADC2.2 exhibited an accumulative pattern in accordance with putrescine content. Moreover, we demonstrated that BrrICE1.1 (Inducer of CBF Expression 1) could directly bind to the BrrADC2.2 promoter, activating BrrADC2.2 to promote the accumulation of putrescine, which was verified by RNAi and overexpression analyses for both BrrADC2.2 and BrrICE1.1 using transgenic hair root. The function of putrescine in turnip was further analyzed by exogenous application putrescine and its inhibitor DL-α-(Difluoromethyl) arginine (DFMA) under freezing tolerance. In addition, the BrrICE1.1 was found to be involved in the ICE1-CBF pathway to increase the freezing stress of turnip. CONCLUSIONS BrrICE1.1 could bind the promoter of BrrADC2.2 or CBFs to participate in freezing tolerance of turnip by transcriptomics and targeted metabolomics analyses. This study revealed the regulatory network of the freezing tolerance process in turnip and increased our understanding of the plateau crops response to extreme environments in Tibet.
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Affiliation(s)
- Xin Yin
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Science, Kunming, 650204, China
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yunqiang Yang
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Science, Kunming, 650204, China
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
| | - Yanqiu Lv
- Changchun Normal University, Changchun, 130032, China
| | - Yan Li
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Science, Kunming, 650204, China
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Danni Yang
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Science, Kunming, 650204, China
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yanling Yue
- College of Landscape and Horticulture, Yunnan Agricultural University, Kunming, 650201, China
| | - Yongping Yang
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Science, Kunming, 650204, China.
- Plant Germplasm and Genomics Center, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China.
- Institute of Tibetan Plateau Research at Kunming, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China.
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11
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Dai Y, Zhang S, Sun X, Li G, Yuan L, Li F, Zhang H, Zhang S, Chen G, Wang C, Sun R. Comparative Transcriptome Analysis of Gene Expression and Regulatory Characteristics Associated with Different Vernalization Periods in Brassica rapa. Genes (Basel) 2020; 11:E392. [PMID: 32260536 PMCID: PMC7231026 DOI: 10.3390/genes11040392] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 03/17/2020] [Accepted: 04/03/2020] [Indexed: 12/17/2022] Open
Abstract
Brassica rapa is an important Chinese vegetable crop that is beneficial to human health. The primary factor affecting B. rapa yield is low temperature, which promotes bolting and flowering, thereby lowering its commercial value. However, quickened bolting and flowering can be used for rapid breeding. Therefore, studying the underlying molecular mechanism of vernalization in B.rapa is crucial for solving production-related problems. Here, the transcriptome of two B. rapa accessions were comprehensively analyzed during different vernalization periods. During vernalization, a total of 974,584,022 clean reads and 291.28 Gb of clean data were obtained. Compared to the reference genome of B. rapa, 44,799 known genes and 2280 new genes were identified. A self-organizing feature map analysis of 21,035 differentially expressed genes was screened in two B. rapa accessions, 'Jin Wawa' and 'Xiao Baojian'. The analysis indicated that transcripts related to the plant hormone signal transduction, starch and sucrose metabolism, photoperiod and circadian clock, and vernalization pathways changed notably at different vernalization periods. Moreover, different expression patterns of TPS, UGP, CDF, VIN1, and seven hormone pathway genes were observed during vernalization between the two accessions. The transcriptome results of this study provide a new perspective on the changes that occur during B. rapavernalization, as well as serve as an excellent reference for B. rapa breeding.
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Affiliation(s)
- Yun Dai
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
- Vegetable Genetics and Breeding Laboratory, College of Horticulture, Anhui Agricultural University, Hefei 230036, China; (L.Y.); (G.C.)
| | - Shujiang Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Xiao Sun
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Guoliang Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Lingyun Yuan
- Vegetable Genetics and Breeding Laboratory, College of Horticulture, Anhui Agricultural University, Hefei 230036, China; (L.Y.); (G.C.)
| | - Fei Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Hui Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Shifan Zhang
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
| | - Guohu Chen
- Vegetable Genetics and Breeding Laboratory, College of Horticulture, Anhui Agricultural University, Hefei 230036, China; (L.Y.); (G.C.)
| | - Chenggang Wang
- Vegetable Genetics and Breeding Laboratory, College of Horticulture, Anhui Agricultural University, Hefei 230036, China; (L.Y.); (G.C.)
| | - Rifei Sun
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (Y.D.); (S.Z.); (X.S.); (G.L.); (F.L.); (H.Z.); (S.Z.)
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12
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Zheng Y, Luo L, Gao Z, Liu Y, Chen Q, Kong X, Yang Y. Grafting induces flowering time and tuber formation changes in Brassica species involving FT signalling. PLANT BIOLOGY (STUTTGART, GERMANY) 2019; 21:1031-1038. [PMID: 31267637 DOI: 10.1111/plb.13024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 06/26/2019] [Indexed: 06/09/2023]
Abstract
Brassica species are widely cultivated and important biennial and annual crops. The transition from vegetative to reproductive development in Brassica species is critical in agriculture and horticulture. Grafting is a useful tool for improving agricultural production and investigating the movement of long-range signals. Here we established a hypocotyl micrografting system in B. rapa crops and successfully grafted the rootstock of turnip onto many different scion genotypes. Grafting with turnip rootstock prolonged vegetative growth, delayed flowering and improved seed yield in rapeseed. The late-flowering turnip rootstock could delay flowering of the scion of the early-flowering turnip accession. The BrrFLC1 (FLOWERING LOCUS C1 in B. rapa) transcript levels and H3K4me3 levels at the BrrFLC1 locus were up-regulated and subsequently suppressed the downstream FT (FLOWERING LOCUS T) signals in leaves of the scion to delay flowering. Vernalization treatment can efficiently promote flowering time in turnip. The non-vernalised turnip flowered early after grafting onto the rootstock of the vernalised turnip, which was accompanied by high levels of FT homologue expression in leaves of the scion. Hypocotyl excision experiments revealed that the process of tuber formation was suppressed by removing the hypocotyl tissue, which in turn repressed the expression of tuberization-related genes. Our findings suggest that the rootstock generates mobile signals that are transported from the rootstock to the scion to fine-tune FT signalling and modulate flowering time.
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Affiliation(s)
- Y Zheng
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
- University of Chinese Academy of Sciences, Beijing, China
| | - L Luo
- School of Ecology and Environmental Science, Yunnan University, Kunming, China
| | - Z Gao
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Y Liu
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
| | - Q Chen
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
| | - X Kong
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
| | - Y Yang
- Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, China
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13
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Natarajan B, Kondhare KR, Hannapel DJ, Banerjee AK. Mobile RNAs and proteins: Prospects in storage organ development of tuber and root crops. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2019; 284:73-81. [PMID: 31084881 DOI: 10.1016/j.plantsci.2019.03.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Revised: 03/21/2019] [Accepted: 03/25/2019] [Indexed: 05/04/2023]
Abstract
Storage tuber and root crops make up a significant portion of the world's subsistence food supply. Because of their importance in food security, yield enhancement has become a priority. A major focus has been to understand the biology of belowground storage organ development. Considerable insights have been gained studying tuber development in potato. We now know that two mobile signals, a full-length mRNA, StBEL5, and a protein, StSP6A, play pivotal roles in regulating tuber development. Under favorable conditions, these signals move from leaves to a belowground modified stem (stolon) and regulate genes that activate tuberization. Overexpression of StBEL5 or StSP6A increases tuber yield even under non-inductive conditions. The mRNAs of two close homologs of StBEL5, StBEL11 and StBEL29, are also known to be mobile but act as repressors of tuberization. Polypyrimidine tract-binding proteins (PTBs) are RNA-binding proteins that facilitate the movement of these mRNAs. Considering their role in tuberization, it is possible that these mobile signals play a major role in storage root development as well. In this review, we explore the presence of these signals and their relevance in the development and yield potential of several important storage root crops.
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Affiliation(s)
- Bhavani Natarajan
- Indian Institute of Science Education and Research (IISER), Biology Division, Pune, 411008, India
| | - Kirtikumar R Kondhare
- Indian Institute of Science Education and Research (IISER), Biology Division, Pune, 411008, India
| | - David J Hannapel
- Plant Biology Major, 253 Horticulture Hall, Iowa State University (ISU), Ames, IA, United States
| | - Anjan K Banerjee
- Indian Institute of Science Education and Research (IISER), Biology Division, Pune, 411008, India.
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14
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Post-transcriptional Regulation of FLOWERING LOCUS T Modulates Heat-Dependent Source-Sink Development in Potato. Curr Biol 2019; 29:1614-1624.e3. [PMID: 31056391 DOI: 10.1016/j.cub.2019.04.027] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 03/27/2019] [Accepted: 04/10/2019] [Indexed: 11/23/2022]
Abstract
Understanding tuberization in the major crop plant potato (Solanum tuberosum L.) is of importance to secure yield even under changing environmental conditions. Tuber formation is controlled by a homolog of the floral inductor FLOWERING LOCUS T, referred to as SP6A. To gain deeper insights into its function, we created transgenic potato plants overexpressing a codon-optimized version of SP6A, SP6Acop, to avoid silencing effects. These plants exhibited extremely early tuberization at the juvenile stage, hindering green biomass development and indicating a tremendous shift in the source sink balance. The meristem identity was altered in dormant buds of transgenic tubers. This strong phenotype, not being reported so far for plants overexpressing an unmodified SP6A, could be due to post-transcriptional regulation. In fact, a putative SP6A-specific small regulatory RNA was identified in potato. It was effectively repressing SP6A mRNA accumulation in transient assays as well as in leaves of young potato plants prior to tuber formation. SP6A expression is downregulated under heat, preventing tuberization. The molecular mechanism has not been elucidated yet. We showed that this small RNA is strongly upregulated under heat. The importance of the small RNA was demonstrated by overexpression of a target mimicry construct, which led to an increased SP6A expression, enabling tuberization even under continuous heat conditions, which abolished tuber formation in the wild-type. Thus, our study describes an additional regulatory mechanism for SP6A besides the well-known pathway that integrates both developmental and environmental signals to control tuberization and is therefore a promising target for breeding of heat-tolerant potato.
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