Functional Diversification of Grapevine MYB5a and MYB5b in the Control of Flavonoid Biosynthesis in a Petunia Anthocyanin Regulatory Mutant

AbstractAlternative splicing (AS) is pervasive in mammalian genomes, yet cross-species comparisons have been largely restricted to adult tissues and the functionality of most AS events remains unclear. We assessed AS patterns across pre- and postnatal development of seven organs in six mammals and a bird. Our analyses revealed that developmentally dynamic AS events, which are especially prevalent in the brain, are substantially more conserved than nondynamic ones. Cassette exons with increasing inclusion frequencies during development show the strongest signals of conserved and regulated AS. Newly emerged cassette exons are typically incorporated late in testis development, but those retained during evolution are predominantly brain specific. Our work suggests that an intricate interplay of programs controlling gene expression levels and AS is fundamental to organ development, especially for the brain and heart. In these regulatory networks, AS affords substantial functional diversification of genes through the generation of tissue- and time-specific isoforms from broadly expressed genes.

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Kinetin-Mediated Stimulation of Accumulation of Buckwheat Flavonoids in the Dark

Zeitschrift für Naturforschung C ◽

10.1515/znc-1983-9-1008 ◽

1983 ◽

Vol 38 (9-10) ◽

pp. 711-718 ◽

Cited By ~ 16

Author(s):

U. Margna ◽

T. Vainjärv

Keyword(s):

Anthocyanin Biosynthesis ◽

Flavonoid Biosynthesis ◽

Accumulation Rates ◽

Sharp Rise ◽

Short Treatment ◽

Exogenous Substrate ◽

Percent Increase ◽

High Level ◽

Fold Stimulation ◽

Stimulation Of

A short treatment of excised buckwheat cotyledons with a solution of kinetin lead to an up to 9-fold stimulation of anthocyanin biosynthesis, to an about 50 percent increase in the accumulation of rutin, and to an about 30 percent increase, on the average, in the accumulation of C-glycosylflavones in the treated material during its posttreatment incubation in the dark. When the treated cotyledons were incubated in a solution of ʟ--phenylalanine anthocyanin accumulation in the dark practically attained the same high level as it was observed in the illuminated cotyledons fed with exogenous ʟ--phenylalanine. In experiments with l4C-labelled L-phenylalanine kinetin induced a sharp rise in the labelling (resp. in the utilization of exogenous substrate for biosynthesis) of anthocyanins and rutin in the dark and a slight increase in the radioactivity of C-glycosylflavones. Similar labelling changes occurred in the illuminated cotyledons. However, both kinetin and light still more effectively promoted biosynthetic use of the endogenous substrate. As a result the relative portion of flavonoids formed from exogenous L-phenylalanine under these conditions showed a decrease as compared with the ratio of precursor use in the untreated cotyledons. The results show that low accumulation rates of anthocyanins and other flavonoids in the dark are conditioned by the limited access of substrate (ʟ--phenylalanine) molecules to the flavonoid enzymes lending further support to the idea that flavonoid biosynthesis is normally controlled at the substrate rather than at the enzymic level.

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Androgen and glucocorticoid receptor direct distinct transcriptional programs by receptor-specific and shared DNA binding sites

Nucleic Acids Research ◽

10.1093/nar/gkab185 ◽

2021 ◽

Vol 49 (7) ◽

pp. 3856-3875

Author(s):

Marina Kulik ◽

Melissa Bothe ◽

Gözde Kibar ◽

Alisa Fuchs ◽

Stefanie Schöne ◽

...

Keyword(s):

Gene Regulation ◽

Transcription Factor ◽

Dna Binding ◽

Receptor Binding ◽

Binding Sites ◽

Specific Gene ◽

Functional Diversification ◽

Enhancer Activity ◽

Sequence Composition

Abstract The glucocorticoid (GR) and androgen (AR) receptors execute unique functions in vivo, yet have nearly identical DNA binding specificities. To identify mechanisms that facilitate functional diversification among these transcription factor paralogs, we studied them in an equivalent cellular context. Analysis of chromatin and sequence suggest that divergent binding, and corresponding gene regulation, are driven by different abilities of AR and GR to interact with relatively inaccessible chromatin. Divergent genomic binding patterns can also be the result of subtle differences in DNA binding preference between AR and GR. Furthermore, the sequence composition of large regions (>10 kb) surrounding selectively occupied binding sites differs significantly, indicating a role for the sequence environment in guiding AR and GR to distinct binding sites. The comparison of binding sites that are shared shows that the specificity paradox can also be resolved by differences in the events that occur downstream of receptor binding. Specifically, shared binding sites display receptor-specific enhancer activity, cofactor recruitment and changes in histone modifications. Genomic deletion of shared binding sites demonstrates their contribution to directing receptor-specific gene regulation. Together, these data suggest that differences in genomic occupancy as well as divergence in the events that occur downstream of receptor binding direct functional diversification among transcription factor paralogs.

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NtbHLH1, a JAF13-like bHLH, interacts with NtMYB6 to enhance proanthocyanidin accumulation in Chinese Narcissus

BMC Plant Biology ◽

10.1186/s12870-021-03050-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yuxin Fan ◽

Jiayu Peng ◽

Jiacheng Wu ◽

Ping Zhou ◽

Ruijie He ◽

...

Keyword(s):

Flavonoid Biosynthesis ◽

Transcriptional Level ◽

Flavonoid Pathway ◽

Regulation Of Expression ◽

Over Expression ◽

Expression Of Genes ◽

Genes Encoding ◽

Regulatory Complex ◽

Positive Regulators ◽

R2r3 Myb

Abstract Background Flavonoid biosynthesis in plants is primarily regulated at the transcriptional level by transcription factors modulating the expression of genes encoding enzymes in the flavonoid pathway. One of the most studied transcription factor complexes involved in this regulation consists of a MYB, bHLH and WD40. However, in Chinese Narcissus (Narcissus tazetta L. var. chinensis), a popular monocot bulb flower, the regulatory mechanism of flavonoid biosynthesis remains unclear. Results In this work, genes related to the regulatory complex, NtbHLH1 and a R2R3-MYB NtMYB6, were cloned from Chinese Narcissus. Phylogenetic analysis indicated that NtbHLH1 belongs to the JAF13 clade of bHLH IIIf subgroup, while NtMYB6 was highly homologous to positive regulators of proanthocyanidin biosynthesis. Both NtbHLH1 and NtMYB6 have highest expression levels in basal plates of Narcissus, where there is an accumulation of proanthocyanidin. Ectopic over expression of NtbHLH1 in tobacco resulted in an increase in anthocyanin accumulation in flowers, and an up-regulation of expression of the endogenous tobacco bHLH AN1 and flavonoid biosynthesis genes. In contrast, the expression level of LAR gene was significantly increased in NtMYB6-transgenic tobacco. Dual luciferase assays showed that co-infiltration of NtbHLH1 and NtMYB6 significantly activated the promoter of Chinese Narcissus DFR gene. Furthermore, a yeast two-hybrid assay confirmed that NtbHLH1 interacts with NtMYB6. Conclusions Our results suggest that NtbHLH1 may function as a regulatory partner by interacting directly with NtMYB6 to enhance proanthocyanidin accumulation in Chinese Narcissus.

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Drought Resistance in Qingke Involves a Reprogramming of the Phenylpropanoid Pathway and UDP-Glucosyltransferase Regulation of Abiotic Stress Tolerance Targeting Flavonoid Biosynthesis

Journal of Agricultural and Food Chemistry ◽

10.1021/acs.jafc.0c07810 ◽

2021 ◽

Author(s):

Congping Xu ◽

Lingling Wei ◽

Sishu Huang ◽

Chunbao Yang ◽

Yulin Wang ◽

...

Keyword(s):

Abiotic Stress ◽

Stress Tolerance ◽

Drought Resistance ◽

Abiotic Stress Tolerance ◽

Phenylpropanoid Pathway ◽

Flavonoid Biosynthesis

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Evolution and functional diversification of the small heat shock protein/α-crystallin family in higher plants

Planta ◽

10.1007/s00425-011-1575-9 ◽

2011 ◽

Vol 235 (6) ◽

pp. 1299-1313 ◽

Cited By ~ 42

Author(s):

Hernán Gabriel Bondino ◽

Estela Marta Valle ◽

Arjen ten Have

Keyword(s):

Heat Shock ◽

Heat Shock Protein ◽

Higher Plants ◽

Small Heat Shock Protein ◽

Functional Diversification

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Transcriptome and metabolome analyses revealing the potential mechanism of seed germination in Polygonatum cyrtonema

Scientific Reports ◽

10.1038/s41598-021-91598-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Rong Liu ◽

Jing Lu ◽

Jiayi Xing ◽

Mei Du ◽

Mingxiu Wang ◽

...

Keyword(s):

Seed Germination ◽

Organic Acids ◽

Plant Hormones ◽

Regulatory Networks ◽

Amylase Activity ◽

Flavonoid Biosynthesis ◽

Market Demand ◽

Potential Mechanism ◽

Flavonoid Synthesis ◽

Germinated Seeds

AbstractPolygonatum cyrtonema Hua (Huangjing, HJ) has medicinal and edible value in China. However, the seeds of this plant are naturally difficult to germinate. Therefore, to elucidate the mechanism underlying the germination of this plant in order to meet the market demand, the metabolomic and transcriptomic analyses were performed in this study. We observed that plant hormones and α-amylase activity were differentially regulated when comparing germinated and un-germinated seeds. In addition, the metabolites related to phenylpropanoid and flavonoid biosynthesis were significantly up-accumulated in germinated seeds. Hydroxycinnamoyl derivatives and organic acids were observed to be significantly decreased during germination. The results of this study suggested that compared to un-germinated seeds, germinated seeds promote flavonoid synthesis and inhibit lignin synthesis which could be beneficial to the germination of HJ seeds. Furthermore, these results suggested that starch if hydrolyzed into glucose, which could provide the necessary energy for germination. Our results may help to establish a foundation for further research investigating the regulatory networks of seed germination and may facilitate the propagation of HJ seeds.

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Comparative Transcriptome Analysis Reveals Key Genes and Pathways Involved in Prickle Development in Eggplant

Genes ◽

10.3390/genes12030341 ◽

2021 ◽

Vol 12 (3) ◽

pp. 341

Author(s):

Lei Zhang ◽

Haoyun Sun ◽

Tao Xu ◽

Tianye Shi ◽

Zongyun Li ◽

...

Keyword(s):

Transcriptome Analysis ◽

Morphological Analysis ◽

Molecular Mechanisms ◽

Flavonoid Biosynthesis ◽

Phenotypic Characterization ◽

Comparative Transcriptome ◽

Hub Genes ◽

Breeding Programs ◽

Comparative Transcriptome Analysis ◽

Key Pathways

Eggplant is one of the most important vegetables worldwide. Prickles on the leaves, stems and fruit calyxes of eggplant may cause difficulties during cultivation, harvesting and transportation, and therefore is an undesirable agronomic trait. However, limited knowledge about molecular mechanisms of prickle morphogenesis has hindered the genetic improvement of eggplant. In this study, we performed the phenotypic characterization and transcriptome analysis on prickly and prickleless eggplant genotypes to understand prickle development at the morphological and molecular levels. Morphological analysis revealed that eggplant prickles were multicellular, lignified and layered organs. Comparative transcriptome analysis identified key pathways and hub genes involved in the cell cycle as well as flavonoid biosynthetic, photosynthetic, and hormone metabolic processes during prickle development. Interestingly, genes associated with flavonoid biosynthesis were up-regulated in developing prickles, and genes associated with photosynthesis were down-regulated in developing and matured prickles. It was also noteworthy that several development-related transcription factors such as bHLH, C2H2, MYB, TCP and WRKY were specifically down- or up-regulated in developing prickles. Furthermore, four genes were found to be differentially expressed within the Pl locus interval. This study provides new insights into the regulatory molecular mechanisms underlying prickle morphogenesis in eggplant, and the genes identified might be exploited in breeding programs to develop prickleless eggplant cultivars.

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