transcription factor HES-1; class B basic helix-loop-helix protein 39; bHLHb39; Hairy & enhancer of split 1; Hairy homolog; Hairy-like protein; hHL (HES1, BHLHB39, HL, HRY)

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Function

transcriptional repressor of genes that require a bHLH protein for their transcription
may act as a negative regulator of myogenesis by inhibiting the functions of MYOD1 & ASH1
binds DNA on N-box motifs: 5'-CACNAG-3' with high affinity & on E-box motifs: 5'-CANNTG-3' with low affinity (putative)
may play a role in a functional FA core complex response to DNA cross-link damage, being required for the stability & nuclear localization of FA core complex proteins, as well as for FANCD2 monoubiquitination in response to DNA damage
transcription repression requires formation of a complex with a corepressor protein of the groucho/TLE family
- interacts (via WPRW motif) with TLE1, & more weakly with TLE2
interacts with HES6 (putative)
interacts with SIRT1
interacts with an FA complex, composed of FANCA, FANCF, FANCG & FANCL, but not of FANCC, nor FANCE
gene is downstream target of notch signalling

has a particular type of basic domain (presence of a helix-interrupting proline) that binds to the N-box (CACNAG), rather than the canonical E-box (CANNTG)
the C-terminal WRPW motif is a transcriptional repression domain necessary for the interaction with groucho/TLE family members, transcriptional corepressors recruited to specific target DNA by Hairy-related proteins (putative)
the bHLH, as well as cooperation between the central Orange domain & the C-terminal WRPW motif, is required for transcriptional repressor activity (putative)
contains 1 basic helix-loop-helix (bHLH) domain
contains 1 Orange domain