Basic helix–loop–helix

<p>A basic helix–loop–helix (bHLH) is a <a href="/facts/Protein/Jxmagu3E">protein</a> <a href="/facts/Structural_motif/g8EBDBGW">structural motif</a> that characterizes one of the largest families of dimerizing <a href="/facts/Transcription_factors/wro0DPHe">transcription factors</a>.  The word "basic" does not refer to complexity but to the chemistry of the motif because transcription factors in general contain <a href="/facts/Base_(chemistry)/M9wA7qeM">basic</a> <a href="/facts/Amino_acid/WDxYwBny">amino acid</a> residues in order to facilitate <a href="/facts/DNA/nB89Iauz">DNA</a> binding.
</p><p>bHLH transcription factors are often important in development or cell activity. For one, BMAL1-Clock (also called <a href="/facts/ARNTL/1hULhtLT">ARNTL</a>) is a core transcription complex in the molecular <a href="/facts/Circadian_clock/ckgjf1h5">circadian clock</a>. Other genes, like <a href="/facts/C-Myc/7FGlAtFk">c-Myc</a> and <a href="/facts/HIF-1/t149wfy6">HIF-1</a>, have been linked to <a href="/facts/Cancer/PVW6n1D0">cancer</a> due to their effects on cell growth and metabolism.
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Basic helix–loop–helix open-in-new

Basic helix–loop–helix