Activator-to-repressor conversion of T-box transcription factors by the Ripply family of Groucho/TLE-associated mediators.

ABSTRACT: The T-box family of transcription factors, defined by a conserved DNA binding domain called the T-box, regulate various aspects of embryogenesis by activating and/or repressing downstream genes. In spite of the biological significance of the T-box proteins, how they regulate transcription remains to be elucidated. Here we show that the Groucho/TLE-associated protein Ripply converts T-box proteins from activators to repressors. In cultured cells, zebrafish Ripply1, an essential component in somite segmentation, and its structural relatives, Ripply2 and -3, suppress the transcriptional activation mediated by the T-box protein Tbx24, which is coexpressed with ripply1 during segmentation. Ripply1 associates with Tbx24 and converts it to a repressor. Ripply1 also antagonizes the transcriptional

SUBMITTER: Kawamura A 

PROVIDER: S-EPMC2423164 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature