描述
The pIB/V5-His TOPO® TA Expression Kit offers five-minute cloning of Taq-amplified PCR products directly into the pIB/V5-His-TOPO expression vector. In addition to being TOPO Cloning ready, pIB/V5-His-TOPO includes:

? The OpIE2 promoter for constitutive expression
? The Blasticidin resistance gene for rapid selection of stably transfected cell lines in two weeks
? C-terminal V5 epitope and polyhistidine (6xHis) sequence for detection with Invitrogen's Anti-V5 Antibody and rapid purification using nickel-chelating resin

表達(dá)水平
The OpIE2 promoter provides relatively high levels of constitutive expression, although not all proteins will express as high as might be expected from baculovirus late promoters such as polyhedrin or very late promoters such as p10 (Jarvis et al., 1996).
However, some researchers have found that the InsectSelect? System expresses some proteins better than baculovirus systems. To date, reported expression levels range from 1-2 μg/ml (human IL-6; Invitrogen) to 8-10 μg/ml (human melanotransferrin) (Hegeduset al., 1999).