RING-CH finger, H2 subclass (C4HC3-type), found in membrane-associated RING-CH10 (MARCH10)
MARCH10, also known as membrane-associated RING finger protein 10, membrane-associated RING-CH protein X (MARCH-X), or RING finger protein 190 (RNF190), is a microtubule-associated E3 ubiquitin ligase in developing spermatids and is involved in spermiogenesis by regulating the formation and maintenance of the flagella. It is localized to the principal piece of elongating spermatids. Unlike other MARCH proteins, MARCH10 is predicted to have no transmembrane spanning region. It harbors a C4HC3-type RING-CH finger, also known as vRING or RINGv, a variant of C3H2C3-type RING-H2 finger, that is responsible for its E3 activity.
Comment:based on the structure of human MARCH8 with bound Zn2+ ions through its RING-CH finger
Comment:RING-CH finger (C4HC3-type)
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 fingers found in MARCH proteins have an unusual arrangement of zinc-coordinating residues: The conserved helix complete with tryptophan at the C-terminal end is present but the cysteines and histidines are arranged in the sequence as C4HC3-type, rather than the typical C3H2C3-type in RING-H2 finger.
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