The ORF in the control region of the female-transmitted Mytilus mtDNA codes for a protein.

Bivalve species with doubly uniparental inheritance of mitochondria have been shown to contain additional mtDNA-encoded proteins suspected to be involved in sex-specific transmission of the female (F) and male (M) mitochondrial genomes. This is true for freshwater mussels and marine clams but was still unclear for marine mussel Mytilus spp. Here we present evidence that a F mtDNA-specific open reading frame (ORF) identified in the control region of M. edulis codes for a protein. The protein was detected, using western blots, in both female and male mantle tissues, which contain the gonads. The protein was also localized, using immunochemistry, in sperm mitochondria.