RING finger, HC subclass, found in RING finger protein unkempt (UNK), unkempt-like (UNKL), and similar proteins
UNK, also known as zinc finger CCCH domain-containing protein 5, is a metazoan-specific zinc finger protein enriched in embryonic brains. It may play a broad regulatory role during the formation of the central nervous system (CNS). It is a sequence-specific RNA-binding protein required for early neuronal morphology. UNK is a neurogenic component of the mTOR pathway, and functions as a negative regulator of the timing of photoreceptor differentiation. It also specifically binds to Brg/Brm-associated factor BAF60b and promotes its ubiquitination in a Rac1-dependent manner. UNKL, also known as zinc finger CCCH domain-containing protein 5-like, is a putative E3 ubiquitin-protein ligase that may participate in a protein complex showing an E3 ligase activity regulated by RAC1. Both UNK and UNKL contain several tandem CCCH-type zinc fingers at the N-terminus, and a C3HC4-type RING-HC finger at its C-terminus.
Comment:C3HC4-type RING-HC finger consensus motif: C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C, where X is any amino acid and the number of X residues varies in different fingers
Comment:A RING finger typically binds two zinc atoms, with its Cys and/or His side chains in a unique "cross-brace" arrangement.
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