Purification of recombinant AtREV1 proteins. Overproduction and purification of recombinant AtREV1 protein in E. coli. Fractions in each purification step were separated on a 7.5% SDS-polyacrylamide gel, then stained with Coomassie Brilliant Blue. Lane 1, Mr marker (Invitrogen); lanes 2 and 3, total E. coli proteins with (lane 3) or without (lane 2) IPTG induction; lane 4, clear lysate; lane 5, fraction eluted from Ni-affinity column; lane 6, fraction from a heparin affinity column; lane 7, purified fraction from HiTrap Q HP column. Molecular weight is shown on the left.