ATP Binding Cassette (ABC) Transporters are a family of proteins that share fairly conserved ATP binding domains and diverse transmembrane regions. They are found in mutant form in various genetic diseases and are conserved across plants, animals, and prokaryotes (see Hot Papers | A Tale of Two Transporters). Perhaps most startling, though, is the balance sheet. The human's 49 known ABC genes are beat out by fly, worm and mouse (56, 56, and 51 respectively), and are dwarfed by the 129 known Arabidopsis thaliana genes.
--Compiled by Aileen Constans