Members of ABC (ATP-binding cassette) transporter subfamily A are full-length transporters [], which consist of a single long polypeptide chain organised into two tandemly arranged halves. Each half contains a membrane-spanning domain (MSD) followed by a cytoplasmic nucleotide binding domain (NBD) []. ATP-binding cassette sub-family A member 1 (ABCA1) interacts with apo-A1, an extracellular lipid acceptor in the plasma [, ]. ABCA1 is involved in cholesterol efflux from peripheral tissues in a process known as the reverse cholesterol transport (RCT). Mutations in the ABCA1 gene cause Tangier disease, which is an autosomal recessive disorder characterised by a severe reduction in the amount of high density lipoprotein (HDL) in the bloodstream []. Mutations in the ABCA1 gene also cause a defect in the clearance of apoptotic cells by macrophages [, ].
