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A novel partner of Scalloped regulates Hippo signaling via antagonizing Scalloped-Yorkie activity.

ABSTRACT: The Hippo (Hpo) pathway controls tissue growth and organ size by regulating the activity of transcriptional co-activator Yorkie (Yki), which associates with transcription factor Scalloped (Sd) in the nucleus to promote downstream target gene expression. Here we identify a novel protein Sd-Binding-Protein (SdBP)/Tgi, which directly competes with Yki for binding to Sd through its TDU domains and inhibits the Sd-Yki transcriptional activity. We also find that SdBP retains Yki in the nucleus through the association with Yki WW domains via its PPXY motifs. Collectively, we identify SdBP as a novel component of the Hpo pathway, negatively regulating the transcriptional activity of Sd-Yki to restrict tissue growth.

SUBMITTER: Guo T

PROVIDER: S-EPMC3790236 | biostudies-literature | 2013 Oct

REPOSITORIES: biostudies-literature

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A novel partner of Scalloped regulates Hippo signaling via antagonizing Scalloped-Yorkie activity.

Guo Tong T Lu Yi Y Li Peixue P Yin Meng-Xin MX Lv Dekang D Zhang Wenjing W Wang Huizhen H Zhou Zhaocai Z Ji Hongbin H Zhao Yun Y Zhang Lei L

Cell research 20130903 10

The Hippo (Hpo) pathway controls tissue growth and organ size by regulating the activity of transcriptional co-activator Yorkie (Yki), which associates with transcription factor Scalloped (Sd) in the nucleus to promote downstream target gene expression. Here we identify a novel protein Sd-Binding-Protein (SdBP)/Tgi, which directly competes with Yki for binding to Sd through its TDU domains and inhibits the Sd-Yki transcriptional activity. We also find that SdBP retains Yki in the nucleus through ...[more]

PMID: 23999857

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The Hippo effector Yorkie controls normal tissue growth by antagonizing scalloped-mediated default repression.

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