Tomato SlBES1.8 influences leaf morphogenesis by mediating gibberellin metabolism and signaling

Leaf morphogenetic activity determines its shape diversity. However, our knowledge to the regulatory mechanism in maintaining leaf morphogenetic capacity is still limited. In tomato, gibberellin (GA) negatively regulates leaf complexity by shortening the morphogenetic window. We here reported a tomato BRI1-EMS-SUPPRESSOR 1 (BES1) transcription factor, SlBES1.8, that promoted the simplification of leaf pattern in a similar manner as GA functions. Enhanced level of SlBES1.8 dramatically decreased the sensibility of tomato to GA whereas increased the sensibility to the GA biosynthesis inhibitor, PAC. In line with the phenotypic observation, the endogenous bioactive GA contents were increased in OE-SlBES1.8 lines, which certainly promoted the degradation of the GA signaling negative regulator, SlDELLA. Moreover, transcriptomic analysis uncovered a set of overlapping genomic targets of SlBES1.8 and GA, and most of them were regulated in the same way. Expression studies showed the repression of SlBES1.8 to the transcriptions of two GA deactivated genes, SlGA2ox2 and SlGA2ox6, and one GA receptor, SlGID1b-1. Further experiments confirmed the direct regulation of SlBES1.8 to their promoters. On the other hand, SlDELLA physically interacted with SlBES1.8 and further inhibited its transcriptional regulation activity by abolishing SlBES1.8-DNA binding. Conclusively, by mediating GA deactivation and signaling, SlBES1.8 greatly influenced tomato leaf morphogenesis.

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CmMYB#7, an R3 MYB transcription factor, acts as a negative regulator of anthocyanin biosynthesis in chrysanthemum

Journal of Experimental Botany ◽

10.1093/jxb/erz121 ◽

2019 ◽

Vol 70 (12) ◽

pp. 3111-3123 ◽

Cited By ~ 8

Author(s):

Lili Xiang ◽

Xiaofen Liu ◽

Heng Li ◽

Xueren Yin ◽

Donald Grierson ◽

...

Keyword(s):

Transcription Factor ◽

Transcription Factors ◽

Binding Site ◽

Transient Expression ◽

Regulatory Mechanism ◽

Anthocyanin Biosynthesis ◽

Expression Patterns ◽

Negative Regulator ◽

Myb Transcription Factor ◽

Anthocyanin Content

Abstract ‘Jimba’, a well-known white flowered chrysanthemum cultivar, occasionally and spontaneously produces red colored petals under natural cultivation, but there is little information about the molecular regulatory mechanism underlying this process. We analysed the expression patterns of 91 MYB transcription factors in ‘Jimba’ and ‘Turning red Jimba’ and identified an R3 MYB, CmMYB#7, whose expression was significantly decreased in ‘Turning red Jimba’ compared with ‘Jimba’, and confirmed it is a passive repressor of anthocyanin biosynthesis. CmMYB#7 competed with CmMYB6, which together with CmbHLH2 is an essential component of the anthocyanin activation complex, for interaction with CmbHLH2 through the bHLH binding site in the R3 MYB domain. This reduced binding of the CmMYB6–CmbHLH2 complex and inhibited its ability to activate CmDFR and CmUFGT promoters. Moreover, using transient expression assays we demonstrated that changes in the expression of CmMYB#7 accounted for alterations in anthocyanin content. Taken together, our findings illustrate that CmMYB#7 is a negative regulator of anthocyanin biosynthesis in chrysanthemum.

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Positive and Negative Regulation of the Cardiovascular Transcription Factor KLF5 by p300 and the Oncogenic Regulator SET through Interaction and Acetylation on the DNA-Binding Domain

Molecular and Cellular Biology ◽

10.1128/mcb.23.23.8528-8541.2003 ◽

2003 ◽

Vol 23 (23) ◽

pp. 8528-8541 ◽

Cited By ~ 77

Author(s):

Saku Miyamoto ◽

Toru Suzuki ◽

Shinsuke Muto ◽

Kenichi Aizawa ◽

Akatsuki Kimura ◽

...

Keyword(s):

Transcription Factor ◽

Dna Binding ◽

Transcriptional Activation ◽

Affinity Purification ◽

Gene Activation ◽

Negative Regulation ◽

Binding Domain ◽

Negative Regulator ◽

The Other ◽

Dna Binding Domain

ABSTRACT Here we show a novel pathway of transcriptional regulation of a DNA-binding transcription factor by coupled interaction and modification (e.g., acetylation) through the DNA-binding domain (DBD). The oncogenic regulator SET was isolated by affinity purification of factors interacting with the DBD of the cardiovascular transcription factor KLF5. SET negatively regulated KLF5 DNA binding, transactivation, and cell-proliferative activities. Down-regulation of the negative regulator SET was seen in response to KLF5-mediated gene activation. The coactivator/acetylase p300, on the other hand, interacted with and acetylated KLF5 DBD, and activated its transcription. Interestingly, SET inhibited KLF5 acetylation, and a nonacetylated mutant of KLF5 showed reduced transcriptional activation and cell growth complementary to the actions of SET. These findings suggest a new pathway for regulation of a DNA-binding transcription factor on the DBD through interaction and coupled acetylation by two opposing regulatory factors of a coactivator/acetylase and a negative cofactor harboring activity to inhibit acetylation.

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Overexpression of bHLH95, a basic helix–loop–helix transcription factor family member, impacts trichome formation via regulating gibberellin biosynthesis in tomato

Journal of Experimental Botany ◽

10.1093/jxb/eraa114 ◽

2020 ◽

Vol 71 (12) ◽

pp. 3450-3462 ◽

Cited By ~ 1

Author(s):

Yao Chen ◽

Dan Su ◽

Jie Li ◽

Shiyu Ying ◽

Heng Deng ◽

...

Keyword(s):

Transcription Factor ◽

Negative Regulator ◽

Gibberellin Biosynthesis ◽

Trichome Density ◽

Solanum Pennellii ◽

Crop Species ◽

Helix Loop Helix ◽

Trichome Formation ◽

Negative Role ◽

Ga Biosynthesis

Abstract Trichomes are epidermal protuberances on aerial parts of plants known to play an important role in biotic and abiotic stresses. To date, our knowledge of the regulation of trichome formation in crop species is very limited. Through phenotyping of the Solanum pennellii×S. lycopersicum (cv. M82) introgression population, we identified the SlbHLH95 transcription factor as a negative regulator of trichome formation in tomato. In line with this negative role, SlbHLH95 displayed a very low expression in stems where trichomes are present at high density. Overexpression of SlbHLH95 resulted in a dramatically reduced trichome density in stems and a significant down-regulation of a set of trichome-related genes. In addition to the lower trichome density, overexpressing lines also showed pleiotropic alterations affecting both vegetative and reproductive development. While most of these phenotypes were reminiscent of gibberellin (GA)-deficient phenotypes, expression studies showed that two GA biosynthesis genes, SlGA20ox2 and SlKS5, are significantly down-regulated in SlbHLH95-OE plants. Moreover, in line with a decrease in active GA content, the glabrous and dwarf phenotypes were rescued by exogenous GA treatment. In addition, yeast one-hybrid and transactivation assays revealed that SlbHLH95 represses the expression of SlGA20ox2 and SlKS5 via direct binding to their promoters. Taken together, our study established a link between SlbHLH95, GA, and trichome formation, and uncovered the role of this gene in modulating GA biosynthesis in tomato.

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The Regulatory Mechanism of Water Activities on Aflatoxins Biosynthesis and Conidia Development, and Transcription Factor AtfB Is Involved in This Regulation

Toxins ◽

10.3390/toxins13060431 ◽

2021 ◽

Vol 13 (6) ◽

pp. 431

Author(s):

Longxue Ma ◽

Xu Li ◽

Xiaoyun Ma ◽

Qiang Yu ◽

Xiaohua Yu ◽

...

Keyword(s):

Transcription Factor ◽

Transcription Factors ◽

Environmental Factors ◽

Health Risks ◽

Sexual Development ◽

Regulatory Mechanism ◽

Food Storage ◽

Economic Losses ◽

Transcriptional Level ◽

Conidia Production

Peanuts are frequently infected by Aspergillus strains and then contaminated by aflatoxins (AF), which brings out economic losses and health risks. AF production is affected by diverse environmental factors, especially water activity (aw). In this study, A. flavus was inoculated into peanuts with different aw (0.90, 0.95, and 0.99). Both AFB1 yield and conidia production showed the highest level in aw 0.90 treatment. Transcriptional level analyses indicated that AF biosynthesis genes, especially the middle- and later-stage genes, were significantly up-regulated in aw 0.90 than aw 0.95 and 0.99. AtfB could be the pivotal regulator response to aw variations, and could further regulate downstream genes, especially AF biosynthesis genes. The expressions of conidia genes and relevant regulators were also more up-regulated at aw 0.90 than aw 0.95 and 0.99, suggesting that the relative lower aw could increase A. flavus conidia development. Furthermore, transcription factors involved in sexual development and nitrogen metabolism were also modulated by different aw. This research partly clarified the regulatory mechanism of aw on AF biosynthesis and A. flavus development and it would supply some advice for AF prevention in food storage.

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Promoter-Proximal Regulatory Elements Involved in oriP-EBNA1-Independent and -Dependent Activation of the Epstein-Barr Virus C Promoter in B-Lymphoid Cell Lines

Journal of Virology ◽

10.1128/jvi.75.13.5796-5811.2001 ◽

2001 ◽

Vol 75 (13) ◽

pp. 5796-5811 ◽

Cited By ~ 31

Author(s):

Tina Nilsson ◽

Henrik Zetterberg ◽

Yuyan Camilla Wang ◽

Lars Rymo

Keyword(s):

Transcription Factor ◽

Epstein Barr Virus ◽

Regulatory Elements ◽

Negative Regulator ◽

Regulatory Sequences ◽

Barr Virus ◽

Group I ◽

Epstein Barr ◽

B Lymphoid ◽

Virus C

ABSTRACT The identification of the cellular factors that control the transcription regulatory activity of the Epstein-Barr virus C promoter (Cp) is fundamental to the understanding of the molecular mechanisms that control virus latent gene expression. Using transient transfection of reporter plasmids in group I phenotype B-lymphoid cells, we have previously shown that the −248 to −55 region (−248/−55 region) of Cp contains elements that are essential fororiPI-EBNA1-dependent as well asoriPI-EBNA1-independent activation of the promoter. We now establish the importance of this region by a detailed mutational analysis of reporter plasmids carrying Cp regulatory sequences together with or without oriPI. The reporter plasmids were transfected into group I phenotype Rael cells and group III phenotype cbc-Rael cells, and the Cp activity measured was correlated with the binding of candidate transcription factors in electrophoretic mobility shift assays and further assessed in cotransfection experiments. We show that the NF-Y transcription factor interacts with the previously identified CCAAT box in the −71/−63 Cp region (M. T. Puglielli, M. Woisetschlaeger, and S. H. Speck, J. Virol. 70:5758–5768, 1996). We also show that members of the C/EBP transcription factor family interact with a C/EBP consensus sequence in the −119/−112 region of Cp and that this interaction is important for promoter activity. A central finding is the identification of a GC-rich sequence in the −99/−91 Cp region that is essential fororiPI-EBNA1-independent as well asoriPI-EBNA1-dependent activity of the promoter. This region contains overlapping binding sites for Sp1 and Egr-1, and our results suggest that Sp1 is a positive and Egr-1 is a negative regulator of Cp activity. Furthermore, we demonstrate that a reporter plasmid that in addition to oriPI contains only the −111/+76 region of Cp still retains the ability to be activated by EBNA1.

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BRN2 is a non-canonical melanoma tumor-suppressor

Nature Communications ◽

10.1038/s41467-021-23973-5 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Michael Hamm ◽

Pierre Sohier ◽

Valérie Petit ◽

Jérémy H. Raymond ◽

Véronique Delmas ◽

...

Keyword(s):

Transcription Factor ◽

Transcription Factors ◽

Tumor Suppressor ◽

The Other ◽

Pi3k Signaling ◽

Melanoma Tumor ◽

Temporal Regulation ◽

Metastatic Colonization ◽

Pou Domain

AbstractWhile the major drivers of melanoma initiation, including activation of NRAS/BRAF and loss of PTEN or CDKN2A, have been identified, the role of key transcription factors that impose altered transcriptional states in response to deregulated signaling is not well understood. The POU domain transcription factor BRN2 is a key regulator of melanoma invasion, yet its role in melanoma initiation remains unknown. Here, in a BrafV600EPtenF/+ context, we show that BRN2 haplo-insufficiency promotes melanoma initiation and metastasis. However, metastatic colonization is less efficient in the absence of Brn2. Mechanistically, BRN2 directly induces PTEN expression and in consequence represses PI3K signaling. Moreover, MITF, a BRN2 target, represses PTEN transcription. Collectively, our results suggest that on a PTEN heterozygous background somatic deletion of one BRN2 allele and temporal regulation of the other allele elicits melanoma initiation and progression.

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A Genetic Screen of the Drosophila X Chromosome for Mutations That Modify Deformed Function

Genetics ◽

10.1093/genetics/150.4.1497 ◽

1998 ◽

Vol 150 (4) ◽

pp. 1497-1511 ◽

Cited By ~ 1

Author(s):

Brian Florence ◽

William McGinnis

Keyword(s):

Transcription Factor ◽

Transcriptional Regulation ◽

Cell Signaling ◽

X Chromosome ◽

Adaptor Protein ◽

Genetic Screen ◽

The Other ◽

Homeotic Gene ◽

Hox Proteins ◽

Hox Gene

Abstract We have screened the Drosophila X chromosome for genes whose dosage affects the function of the homeotic gene Deformed. One of these genes, extradenticle, encodes a homeodomain transcription factor that heterodimerizes with Deformed and other homeotic Hox proteins. Mutations in the nejire gene, which encodes a transcriptional adaptor protein belonging to the CBP/p300 family, also interact with Deformed. The other previously characterized gene identified as a Deformed interactor is Notch, which encodes a transmembrane receptor. These three genes underscore the importance of transcriptional regulation and cell-cell signaling in Hox function. Four novel genes were also identified in the screen. One of these, rancor, is required for appropriate embryonic expression of Deformed and another homeotic gene, labial. Both Notch and nejire affect the function of another Hox gene, Ultrabithorax, indicating they may be required for homeotic activity in general.

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Whole-Genome Analysis of Genes Regulated by the Bacillus subtilis Competence Transcription Factor ComK

Journal of Bacteriology ◽

10.1128/jb.184.9.2344-2351.2002 ◽

2002 ◽

Vol 184 (9) ◽

pp. 2344-2351 ◽

Cited By ~ 110

Author(s):

Mitsuo Ogura ◽

Hirotake Yamaguchi ◽

Kazuo Kobayashi ◽

Naotake Ogasawara ◽

Yasutaro Fujita ◽

...

Keyword(s):

Transcription Factor ◽

Bacillus Subtilis ◽

Genetic Transformation ◽

Dna Microarray ◽

Genome Analysis ◽

Transformation Efficiency ◽

The Other ◽

Whole Genome ◽

Whole Genome Analysis ◽

Microarray Technique

ABSTRACT The Bacillus subtilis competence transcription factor ComK is required for establishment of competence for genetic transformation. In an attempt to study the ComK factor further, we explored the genes regulated by ComK using the DNA microarray technique. In addition to the genes known to be dependent on ComK for expression, we found many genes or operons whose ComK dependence was not known previously. Among these genes, we confirmed the ComK dependence of 16 genes by using lacZ fusions, and three genes were partially dependent on ComK. Transformation efficiency was significantly reduced in an smf disruption mutant, although disruption of the other ComK-dependent genes did not result in significant decreases in transformation efficiency. Nucleotide sequences similar to that of the ComK box were found for most of the newly discovered genes regulated by ComK.

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