Target selectivity of vertebrate notch proteins: Collaboration between discrete domains and CSL-binding site architecture determines activation probability

Chin Tong Ong, Hui Teng Cheng, Li Wei Chang, Toshiyuki Ohtsuka, Ryoichiro Kageyama, Gary D. Stormo, Raphael Kopan

Research output: Contribution to journalArticle

161 Scopus citations

Abstract

All four mammalian Notch proteins interact with a single DNA-binding protein (RBP-jκ), yet they are not equivalent in activating target genes. Parallel assays of three Notch-responsive promoters in several cell lines revealed that relative activation strength is dependent on protein module and promoter context more than the cellular context. Each Notch protein reads binding site orientation and distribution on the promoter differently; Notch1 performs extremely well on paired sites, and Notch3 prefers single sites in conjunction with a proximal zinc finger transcription factor. Although head-head sites can elicit a Notch response on their own, use of CBS (CSL binding site) in tail-tail orientation is context-dependent. Bias for specific DNA elements is achieved by interplay between the N-terminal RAM (RBP-jκ-associated molecule/ankyrin region), which interprets CBS proximity and orientation, and the C-terminal transactivation domain that interacts specifically with the transcription machinery or nearby factors. To confirm the prediction that modular design underscores the evolution of functional divergence between Notch proteins, we generated a synthetic Notch protein (Notch1 ankyrin with Notch3 transactivation domain) that displayed superior signaling strength on the hes5 promoter. Consistent with the prediction that "preferred" targets (Hes1) should respond faster and at lower Notch concentration than other targets, we showed that Hes5-GFP was extinguished fast and recovered slowly, whereas Hes1-GFP was inhibited late and recovered quickly after a pulse of DAPT in metanephroi cultures.

Original languageEnglish
Pages (from-to)5106-5119
Number of pages14
JournalJournal of Biological Chemistry
Volume281
Issue number8
DOIs
StatePublished - Feb 24 2006

Fingerprint Dive into the research topics of 'Target selectivity of vertebrate notch proteins: Collaboration between discrete domains and CSL-binding site architecture determines activation probability'. Together they form a unique fingerprint.

  • Cite this