pAcGFP1-N1載體描述 pAcGFP1-N1 encodes a green fluorescent protein (GFP) from Aequorea coerulescens (excitation maximum = 475 nm; emission maximum = 505 nm). The coding sequence of the AcGFP1 gene contains silent base changes, which correspond to human codon-usage preferences (1). The MCS in pAcGFP1-N1 is between the immediate early promoter of CMV (PCMV IE) and the AcGFP1 coding sequences. Genes cloned into the MCS will be expressed as fusions to the N-terminus of AcGFP1 if they are in the same reading frame as AcGFP1 and there are no intervening stop codons. SV40 polyadenylation signals downstream of the AcGFP1 gene direct proper processing of the 3' end of the AcGFP1 mRNA. The vector backbone also contains an SV40 origin for replication in mammalian cells expressing the SV40 T antigen. A neomycin-resistance cassette (Neor), consisting of the SV40 early promoter, the neomycin/kanamycin resistance gene of Tn5, and polyadenylation signals from the Herpes simplex virus thymidine kinase (HSV TK) gene, allows stably transfected eukaryotic cells to be selected using G418. A bacterial promoter upstream of the gene expresses kanamycin resistance in E. coli. The pAcGFP1-N1 backbone also provides a pUC origin of replication for propagation in E. coli and an f1 origin for single-stranded DNA production.
Fusions to the N terminus of AcGFP1 retain the fluorescent properties of the native protein allowing the localization of the fusion protein in vivo . The target gene should be cloned into pAcGFP1-N1 so that it is in frame with the AcGFP1 coding sequences, with no intervening in-frame stop codons. The inserted gene should include the initiating ATG codon. The recombinant AcGFP1 vector can be transfected into mammalian cells using any standard transfection method. If required, stable transformants can be selected using G418 (2). pAcGFP1-N1 can also be used simply to express AcGFP1 in a cell line of interest (e.g., as a transfection marker). Propagation in E. coli Suitable host strains: DH5α, HB101 and other general purpose strains. Single-stranded DNA production requires
a host containing an F plasmid such as JM101 or XL1-Blue.
Selectable marker: plasmid confers resistance to kanamycin (30 μg/ml) to E. coli hosts.
E. coli replication origin: pUC
Copy number: ≈500
Plasmid incompatibility group: pMB1/ColE1
