Modified RING-CH finger, H2 subclass (C4HC2H-type), found in zinc/RING finger protein 2 (ZNRF2) and similar proteins
ZNRF2, also known as protein Ells2 or RING finger protein 202 (RNF202), is an E3 ubiquitin-protein ligase that is highly expressed in the nervous system during development and is present in presynaptic plasma membranes. It is N-myrisotoylated and is also located in the endosome-lysosome compartment in fibroblasts. It contains an N-terminal MAGE domain, and a special C-terminal domain that combines a zinc finger and a modified C4HC2H-type RING-CH finger, rather than the typical C4HC3-type RING-CH finger, which is a variant of RING-H2 finger. Only the RING finger of the zinc finger-RING finger motif is required for its E3 ubiquitin ligase activity. Together with its sister protein ZNRF1, ZNRF2 regulates the ubiquitous Na+/K+ pump (Na+/K+ATPase).
Comment:A RING finger typically binds two zinc atoms, with its Cys and/or His side chains in a unique "cross-brace" arrangement.
Comment:The RING-CH fingers found in ZNRF proteins are modified as C4HC2H-type RING-CH finger, rather than the typical C4HC3-type RING-CH finger, which is a variant of RING-H2 finger.
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