E3 ubiquitin-protein ligase MARCH9 (membrane-associated RING finger protein 9, membrane-associated RING-CH protein IX, MARCH-IX, RING finger protein 179, MARCH9, RNF179)

Function

• E3 ubiquitin-protein ligase
• ubiquitin conjugation, 3rd step
• may mediate ubiquitination of MHC-1, CD4 & ICAM1, & promote their subsequent endocytosis and sorting to lysosomes via multivesicular bodies

Structure

• homodimer
• contains 1 RING-CH-type zinc finger, required for E3 ligase activity
• isoform lacks RING-CH-type zinc finger, thus no E3 ligase activity, but is able to dimerize with & stabilize isoform 1

Compartment

Golgi membrane, lysosome membrane

Alternative splicing

named isoforms=2

Expression

ubiquitously expressed

More general terms

• E3 ubiquitin ligase
• ring finger protein
• membrane protein

Database

• UniProt: http://www.uniprot.org/uniprot/Q86YJ5.html