Which of the following is not a function of ABC transporters?
ABC transporters are defined as primary active systems utilizing ATP binding and hydrolysis at conserved nucleotide-binding domains to drive uphill movement of substrate. Their tasks include export of lipophilic drugs and xenobiotics by ABCB1, ABCC1, ABCG2 conferring multidrug resistance, phosphatidylcholine flipping by ABCB4 for biliary micelle formation, bile salt export by ABCB11, cholesterol and phospholipid efflux by ABCA1 to apolipoprotein A1 in HDL biogenesis, and peptide delivery by TAP1/TAP2 into endoplasmic reticulum for antigen presentation. In prokaryotes they import sugars, amino
Ref: Locher, Nature 2016, ABC mechanisms; Dean, Genome Res 2001, ABC functions.