What do rhomboids do?

Known, or strongly suspected, rhomboid functions now include the following:

• all eukaryotes have a mitochondrial rhomboid that can regulate mitochondrial function and morphology;
• apicomplexan parasites like Plasmodium and Toxoplasma appear to use rhomboids to cleave cell surface proteins that participate in the host invasion process;
• a rhomboid in the Gram-negative bacterium Providencia stuartii is required for the function of the TatA protein translocation machinery;
• the role of rhomboids in mammals, plants, and many other species is now being investigated by a number of groups. Watch this space!