RING-CH finger, H2 subclass (C4HC3-type), found in membrane-associated MARCH7, MARCH10, and similar proteins
The subfamily includes two closely related membrane-associated RING-CH proteins, MARCH7 and MARCH10, both of which are predicted to have no transmembrane spanning region, but harbor a C4HC3-type RING-CH finger, also known as vRING or RINGv, a variant of C3H2C3-type RING-H2 finger, that is responsible for E3 activity. MARCH7, also known as MARCH-VII, RNF177, or axotrophin, is a ubiquitin E3 ligase expressed in multiple types of cells and tissues, including stem cells and precursor cells, and predominantly localized on the plasma membrane, and cytoplasm. MARCH7 is involved in T cell proliferation and neuronal development. It also participates in the regulation of cytoskeleton re-organization, cellular migration and invasion, cell proliferation, and tumorigenesis in ovarian carcinoma cells. Moreover, MARCH7 modulates nuclear factor kappaB (NF-kappaB) and Wnt/beta-catenin pathways. It has been identified as an authentic target of miR-101. Furthermore, ubiquitinates tau protein in vitro impairing microtubule binding. MARCH10, also known as MARCH-X or RNF190, is a microtubule-associated E3 ubiquitin ligase of developing spermatids. It is localized to the principal piece of elongating spermatids. MARCH10 is involved in spermiogenesis by regulating the formation and maintenance of the flagella in developing spermatids.