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. 2021 Mar;105(4-5):463-482.
doi: 10.1007/s11103-020-01101-z. Epub 2021 Jan 21.

SCARECROW-LIKE3 regulates the transcription of gibberellin-related genes by acting as a transcriptional co-repressor of GAI-ASSOCIATED FACTOR1

Takeshi Ito  1 , Jutarou Fukazawa  2
Affiliations

SCARECROW-LIKE3 regulates the transcription of gibberellin-related genes by acting as a transcriptional co-repressor of GAI-ASSOCIATED FACTOR1

Takeshi Ito et al. Plant Mol Biol. 2021 Mar.

Abstract

SCL3 inhibits transcriptional activity of IDD-DELLA complex by acting as a co-repressor and repression activity is enhanced in the presence of GAF1 in a TOPLESS-independent manner. GRAS [GIBBERELLIN-INSENSITIVE (GAI), REPRESSOR OF ga1-3 (RGA) and SCARECROW (SCR)] proteins are a family of plant-specific transcriptional regulators that play diverse roles in development and signaling. GRAS family DELLA proteins act as growth repressors by inhibiting gibberellin (GA) signaling in response to developmental and environmental cues. DELLAs also act as co-activators of transcription factor GAI-ASSOCIATED FACTOR1 (GAF1)/INDETERMINATE DOMAIN2 (IDD2), the GAF1-DELLA complex activating transcription of GAF1 target genes. GAF1 also interacts with TOPLESS (TPL), a transcriptional co-repressor, in the absence of DELLA, the GAF1-TPL complex repressing transcription of the target genes. SCARECROW-LIKE3 (SCL3), another member of the GRAS family, is thought to inhibit transcriptional activity of the IDD-DELLA complex through competitive interaction with IDD. Here, we also revealed that SCL3 inhibits transcriptional activation by the GAF1-DELLA complex via repression activity rather than via competitive inhibition of the GAF1-DELLA interaction. Moreover, the repression activity of SCL3 was enhanced by GAF1 in a TPL-independent manner. While the GRAS domain of DELLA has transcriptional activation activity, that of SCL3 has repression activity. SCL3 also inhibited transcriptional activity of GAF1-RGA fusion proteins. Results from the co-immunoprecipitation assays and the yeast three-hybrid assay suggested the possibility that SCL3 forms a ternary complex with GAF1 and DELLA. These findings provide important information on DELLA-regulated GA signaling and new insight into the transcriptional repression mechanism.

Keywords: Co-repressor; DELLA; GRAS; IDD; Transcriptional regulation; Transcriptional repression.

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References

    1. Aoyanagi T, Ikeya S, Kobayashi A, Kozaki A (2020) Gene regulation via the combination of transcription factors in the INDETERMINATE DOMAIN and GRAS families. Genes 11:1–18. https://doi.org/10.3390/genes11060613 - DOI
    1. Bai MY, Shang JX, Oh E, Fan M, Bai Y, Zentella R, Sun T, Wang ZY (2012) Brassinosteroid, gibberellin and phytochrome impinge on a common transcription module in Arabidopsis. Nat Cell Biol 14:810–817. https://doi.org/10.1038/ncb2546 - DOI - PubMed - PMC
    1. Bolle C (2004) The role of GRAS proteins in plant signal transduction and development. Planta 218:683–692. https://doi.org/10.1007/s00425-004-1203-z - DOI - PubMed
    1. Causier B, Ashworth M, Guo W, Davies B (2012) The TOPLESS interactome: a framework for gene repression in Arabidopsis. Plant Physiol 158:423–438. https://doi.org/10.1104/pp.111.186999 - DOI - PubMed
    1. Cheng H, Qin L, Lee S, Fu X, Richards DE, Cao D, Luo D, Harberd NP, Peng J (2004) Gibberellin regulates Arabidopsis floral development via suppression of DELLA protein function. Development 131:1055–1064. https://doi.org/10.1242/dev.00992 - DOI - PubMed

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