Mba1 is an inner membrane protein that is part of the mitochondrial protein export machinery. It binds to the large subunit of mitochondrial ribosomes and cooperates with the C-terminal ribosome-binding domain of Oxa1, which is a central component of the insertion machinery of the inner membrane. In the absence of both Mba1 and the C-terminus of Oxa1, mitochondrial translation products fail to be properly inserted into the inner membrane and serve as substrates of the matrix chaperone Hsp70. It is proposed that Mba1 functions as a ribosome receptor that cooperates with Oxa1 in the positioning of the ribosome exit site to the insertion machinery of the inner membrane.
Jiyao W et al.(2023). "The conserved domain database in 2023.",