The role of VvMYBA2r and VvMYBA2w alleles of the MYBA2 locus in the regulation of anthocyanin biosynthesis for molecular breeding of grape ( Vitis spp.) skin coloration

OsmiR535 belongs to the miR156/miR529/miR535 superfamily, a highly conserved miRNA family in plants. OsmiR535 is involved in regulating the cold-stress response, modulating plant development, and determining panicle architecture and grain length. However, the role that OsmiR535 plays in plant responses to drought and salinity are elusive. In the current study, molecular and genetic engineering techniques were used to elucidate the possible role of OsmiR535 in response to NaCl, PEG(Poly ethylene glycol), ABA(Abscisic acid), and dehydration stresses. Our results showed that OsmiR535 is induced under stressed conditions as compared to control. With transgenic and CRISPR/Cas9 knockout system techniques, our results verified that either inhibition or knockout of OsmiR535 in rice could enhance the tolerance of plants to NaCl, ABA, dehydration and PEG stresses. In addition, the overexpression of OsmiR535 significantly reduced the survival rate of rice seedlings during PEG and dehydration post-stress recovery. Our results demonstrated that OsmiR535 negatively regulates the stress response in rice. Moreover, our practical application of CRISPR/Cas9 mediated genome editing created a homozygous 5 bp deletion in the coding sequence of OsmiR535, demonstrating that OsmiR535 could be a useful genetic editing target for drought and salinity tolerance and a new marker for molecular breeding of Oryza sativa.

Download Full-text

Investigation of the role of AcTPR2 in kiwifruit and its response to Botrytis cinerea infection

10.21203/rs.3.rs-46966/v2 ◽

2020 ◽

Author(s):

Zhexin Li ◽

Jian-Bin Lan ◽

Yi-Qing Liu ◽

Li-Wang Qi ◽

Jianmin Tang

Keyword(s):

Disease Resistance ◽

Botrytis Cinerea ◽

Indole Acetic Acid ◽

Phenylalanine Ammonia Lyase ◽

Molecular Breeding ◽

Gray Mold ◽

Virus Induced Gene Silencing ◽

Defensive Enzymes ◽

Endogenous Phytohormones

Abstract Background: Elucidation of the regulatory mechanism of kiwifruit response to gray mold disease caused by Botrytis cinerea can provide the basis for its molecular breeding to impart resistance against this disease. In this study, 'Hongyang' kiwifruit served as the experimental material; the TOPLESS/TOPLESS-RELATED (TPL/TPR) co-repressor gene AcTPR2 was cloned into a pTRV2 vector (AcTPR2-TRV) and the virus-induced gene silencing technique was used to establish the functions of the AcTPR2 gene in kiwifruit resistance to Botrytis cinerea.Results: Virus-induced silencing of AcTPR2 enhanced the susceptibility of kiwifruit to Botrytis cinerea. Defensive enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and phenylalanine ammonia-lyase (PAL) and endogenous phytohormones such as indole acetic acid (IAA), gibberellin (GA3), abscisic acid (ABA), and salicylic acid (SA) were detected. Kiwifruit activated these enzymes and endogenous phytohormones in response to pathogen-induced stress and injury. The expression levels of the IAA signaling genes—AcNIT, AcARF1, and AcARF2—were higher in the AcTPR2-TRV treatment group than in the control. The IAA levels were higher and the rot phenotype was more severe in AcTPR2-TRV kiwifruits than that in the control. These results suggested that AcTPR2 downregulation promotes expression of IAA and IAA signaling genes and accelerates postharvest kiwifruit senescence. Further, Botrytis cinerea dramatically upregulated AcTPR2, indicating that AcTPR2 augments kiwifruit defense against pathogens by downregulating the IAA and IAA signaling genes.Conclusions: The results of the present study could help clarify the regulatory mechanisms of disease resistance in kiwifruit and furnish genetic resources for molecular breeding of kiwifruit disease resistance.

Download Full-text

Investigation of the role of AcTPR2 in kiwifruit and its response to Botrytis cinerea infection

10.21203/rs.3.rs-46966/v4 ◽

2020 ◽

Author(s):

Zhexin Li ◽

Jian-Bin Lan ◽

Yi-Qing Liu ◽

Li-Wang Qi ◽

Jianmin Tang

Keyword(s):

Disease Resistance ◽

Botrytis Cinerea ◽

Indole Acetic Acid ◽

Phenylalanine Ammonia Lyase ◽

Molecular Breeding ◽

Gray Mold ◽

Virus Induced Gene Silencing ◽

Defensive Enzymes ◽

Endogenous Phytohormones

Abstract Background: Elucidation of the regulatory mechanism of kiwifruit response to gray mold disease caused by Botrytis cinerea can provide the basis for its molecular breeding to impart resistance against this disease. In this study, 'Hongyang' kiwifruit served as the experimental material; the TOPLESS/TOPLESS-RELATED (TPL/TPR) co-repressor gene AcTPR2 was cloned into a pTRV2 vector (AcTPR2-TRV) and the virus-induced gene silencing technique was used to establish the functions of the AcTPR2 gene in kiwifruit resistance to Botrytis cinerea.Results: Virus-induced silencing of AcTPR2 enhanced the susceptibility of kiwifruit to Botrytis cinerea. Defensive enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and phenylalanine ammonia-lyase (PAL) and endogenous phytohormones such as indole acetic acid (IAA), gibberellin (GA3), abscisic acid (ABA), and salicylic acid (SA) were detected. Kiwifruit activated these enzymes and endogenous phytohormones in response to pathogen-induced stress and injury. The expression levels of the IAA signaling genes—AcNIT, AcARF1, and AcARF2—were higher in the AcTPR2-TRV treatment group than in the control. The IAA levels were higher and the rot phenotype was more severe in AcTPR2-TRV kiwifruits than that in the control. These results suggested that AcTPR2 downregulation promotes expression of IAA and IAA signaling genes and accelerates postharvest kiwifruit senescence. Further, Botrytis cinerea dramatically upregulated AcTPR2, indicating that AcTPR2 augments kiwifruit defense against pathogens by downregulating the IAA and IAA signaling genes.Conclusions: The results of the present study could help clarify the regulatory mechanisms of disease resistance in kiwifruit and furnish genetic resources for molecular breeding of kiwifruit disease resistance.

Download Full-text

Cloning and Functional Characterization of Dihydroflavonol 4-Reductase Gene Involved in Anthocyanin Biosynthesis of Chrysanthemum

International Journal of Molecular Sciences ◽

10.3390/ijms21217960 ◽

2020 ◽

Vol 21 (21) ◽

pp. 7960

Author(s):

Sun-Hyung Lim ◽

Bora Park ◽

Da-Hye Kim ◽

Sangkyu Park ◽

Ju-Hee Yang ◽

...

Keyword(s):

Developmental Stages ◽

Anthocyanin Biosynthesis ◽

Functional Characterization ◽

Flower Color ◽

Chrysanthemum Morifolium ◽

C Terminus ◽

Reductase Gene ◽

The Difference ◽

Chrysanthemum Morifolium Ramat

Dihydroflavonol 4-reductase (DFR) catalyzes a committed step in anthocyanin and proanthocyanidin biosynthesis by reducing dihydroflavonols to leucoanthocyanidins. However, the role of this enzyme in determining flower color in the economically important crop chrysanthemum (Chrysanthemum morifolium Ramat.) is unknown. Here, we isolated cDNAs encoding DFR from two chrysanthemum cultivars, the white-flowered chrysanthemum “OhBlang” (CmDFR-OB) and the red-flowered chrysanthemum “RedMarble” (CmDFR-RM) and identified variations in the C-terminus between the two sequences. An enzyme assay using recombinant proteins revealed that both enzymes catalyzed the reduction of dihydroflavonol substrates, but CmDFR-OB showed significantly reduced DFR activity for dihydrokaempferol (DHK) substrate as compared with CmDFR-RM. Transcript levels of anthocyanin biosynthetic genes were consistent with the anthocyanin contents at different flower developmental stages of both cultivars. The inplanta complementation assay, using Arabidopsis thaliana dfr mutant (tt3-1), revealed that CmDFR-RM, but not CmDFR-OB, transgenes restored defective anthocyanin biosynthesis of this mutant at the seedling stage, as well as proanthocyanidin biosynthesis in the seed. The difference in the flower color of two chrysanthemums can be explained by the C-terminal variation of CmDFR combined with the loss of CmF3H expression during flower development.

Download Full-text

Transcriptome analysis of radish sprouts hypocotyls reveals the regulatory role of hydrogen-rich water in anthocyanin biosynthesis under UV-A

BMC Plant Biology ◽

10.1186/s12870-018-1449-4 ◽

2018 ◽

Vol 18 (1) ◽

Cited By ~ 7

Author(s):

Xiaoyan Zhang ◽

Nana Su ◽

Li Jia ◽

Jiyuan Tian ◽

Han Li ◽

...

Keyword(s):

Transcriptome Analysis ◽

Anthocyanin Biosynthesis ◽

Regulatory Role ◽

Radish Sprouts

Download Full-text

Quantitative Epigenetics: A New Avenue for Crop Improvement

Epigenomes ◽

10.3390/epigenomes4040025 ◽

2020 ◽

Vol 4 (4) ◽

pp. 25 ◽

Cited By ~ 1

Author(s):

Vijay Gahlaut ◽

Gaurav Zinta ◽

Vandana Jaiswal ◽

Sanjay Kumar

Keyword(s):

Molecular Breeding ◽

Recombinant Inbred Lines ◽

Crop Improvement ◽

Genotyping By Sequencing ◽

Phenotypic Traits ◽

Epigenetic Variation ◽

Epigenome Editing ◽

Epigenetic Diversity ◽

Improvement Programs

Plant breeding conventionally depends on genetic variability available in a species to improve a particular trait in the crop. However, epigenetic diversity may provide an additional tier of variation. The recent advent of epigenome technologies has elucidated the role of epigenetic variation in shaping phenotype. Furthermore, the development of epigenetic recombinant inbred lines (epi-RILs) in model species such as Arabidopsis has enabled accurate genetic analysis of epigenetic variation. Subsequently, mapping of epigenetic quantitative trait loci (epiQTL) allowed association between epialleles and phenotypic traits. Likewise, epigenome-wide association study (EWAS) and epi-genotyping by sequencing (epi-GBS) have revolutionized the field of epigenetics research in plants. Thus, quantitative epigenetics provides ample opportunities to dissect the role of epigenetic variation in trait regulation, which can be eventually utilized in crop improvement programs. Moreover, locus-specific manipulation of DNA methylation by epigenome-editing tools such as clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) can potentially facilitate epigenetic based molecular breeding of important crop plants.

Download Full-text

Apple B-box factors regulate light-responsive anthocyanin biosynthesis genes

Scientific Reports ◽

10.1038/s41598-019-54166-2 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Blue J. Plunkett ◽

Rebecca Henry-Kirk ◽

Adam Friend ◽

Robert Diack ◽

Susanne Helbig ◽

...

Keyword(s):

Anthocyanin Biosynthesis ◽

Dependent Manner ◽

Fruit Colour ◽

Temperature Dependent ◽

Environmental Signals ◽

Over Expression ◽

Ethylene Content ◽

Environmentally Responsive ◽

Anthocyanin Biosynthetic Genes

AbstractEnvironmentally-responsive genes can affect fruit red colour via the activation of MYB transcription factors. The apple B-box (BBX) gene, BBX33/CONSTANS-like 11 (COL11) has been reported to influence apple red-skin colour in a light- and temperature-dependent manner. To further understand the role of apple BBX genes, other members of the BBX family were examined for effects on colour regulation. Expression of 23 BBX genes in apple skin was analysed during fruit development. We investigated the diurnal rhythm of expression of the BBX genes, the anthocyanin biosynthetic genes and a MYB activator, MYB10. Transactivation assays on the MYB10 promoter, showed that BBX proteins 1, 17, 15, 35, 51, and 54 were able to directly function as activators. Using truncated versions of the MYB10 promoter, a key region was identified for activation by BBX1. BBX1 enhanced the activation of MYB10 and MdbHLH3 on the promoter of the anthocyanin biosynthetic gene DFR. In transformed apple lines, over-expression of BBX1 reduced internal ethylene content and altered both cyanidin concentration and associated gene expression. We propose that, along with environmental signals, the control of MYB10 expression by BBXs in ‘Royal Gala’ fruit involves the integration of the expression of multiple BBXs to regulate fruit colour.

Download Full-text

Comparative Transcriptome Analysis Reveals Effects of Exogenous Hematin on Anthocyanin Biosynthesis during Strawberry Fruit Ripening

International Journal of Genomics ◽

10.1155/2016/6762731 ◽

2016 ◽

Vol 2016 ◽

pp. 1-14 ◽

Cited By ~ 5

Author(s):

Yi Li ◽

Huayin Li ◽

Fengde Wang ◽

Jingjuan Li ◽

Yihui Zhang ◽

...

Keyword(s):

Transcriptome Analysis ◽

Regulatory Networks ◽

Anthocyanin Biosynthesis ◽

Anthocyanin Synthesis ◽

Control Group ◽

Anthocyanin Content ◽

Color Development ◽

Strawberry Fruit Ripening ◽

Positive Effect

Anthocyanin in strawberries has a positive effect on fruit coloration. In this study, the role of exogenous hematin on anthocyanin biosynthesis was investigated. Our result showed that the white stage of strawberries treated with exogenous hematin had higher anthocyanin content, compared to the control group. Among all treatments, 5 μM of hematin was the optimal condition to promote color development. In order to explore the molecular mechanism of fruit coloring regulated by hematin, transcriptomes in the hematin- and non-hematin-treated fruit were analyzed. A large number of differentially expressed genes (DEGs) were identified in regulating anthocyanin synthesis, including the DEGs involved in anthocyanin biosynthesis, hormone signaling transduction, phytochrome signaling, starch and sucrose degradation, and transcriptional pathways. These regulatory networks may play an important role in regulating the color process of strawberries treated with hematin. In summary, exogenous hematin could promote fruit coloring by increasing anthocyanin content in the white stage of strawberries. Furthermore, transcriptome analysis suggests that hematin-promoted fruit coloring occurs through multiple related metabolic pathways, which provides valuable information for regulating fruit color via anthocyanin biosynthesis in strawberries.

Download Full-text