ABSTRACT
Objective To construct eukaryotic enhanced green fluorescent protein (EGFP) expressing recombinant plasmid, pEGFP-C1-hnRNP A1, which contains coding sequence of human hnRNP A1 (heterogeneous nuclear ribonucleo-protein A1), and to perform cellular localization analysis of EGFP tagged hnRNP A1 under stress. Methods Total RNA was isolated from HeLa cell used for synthesis of first-strand cDNAs using reverse primers that are specific for the 3′-un-translated region of hnRNP A1. hnRNP A1 gene fragments were then amplified by touch-down PCR from those cDNAs and inserted into pEGFP-C1 fluorescent bearing vector through EcoRⅠ/BamHⅡdouble enzyme digestion and T4 DNA Ligase connection. The recombinant pEGFP-C1-hnRNP A1 plasmid was transfected into HeLa cells and green fluorescent tagged fusion proteins was examined by Western blot and confocal fluorescence microscopy. Co-localization of EGFP-hnRNP A 1 with poly (A)+mRNA (the marker of the stress granules), or DCP1a (the marker of processome) were detected by RNA fluores-cence in situ hybridization and immunofluorescence. Results The pEGFP-C1-hnRNP A1 was sequenced and digested cor-rectly by restriction single/double enzyme. The green fluorescent fusion protein was also detected in transfected HeLa cell by Western blot and confocal fluorescence microscopy. EGFP-hnRNP A1 co-localizes with poly(A)+mRNA, but not DCP1a. Conclusion Recombinant eukaryotic plasmid of pEGFP-C1-hnRNP A1 was constructed successfully and expressed effec-tively. EGFP tagged hnRNP A1 takes part in forming stress granules.
ABSTRACT
Objective:To construct eukaryotic expression vectors pEGFP-N2/MafA and pEGFP-C1/MafA,encoding the mouse musculus v-maf musculoaponeurotic fibrosarcoma oncogene family,protein A(MafA)gene,for the further research of its expression in HepG-2 cells.Methods:pRNA of the mouse MafA gene was distilled by RT-PCR from the mouse,and inserted into Hind Ⅲand SalⅠrestriction sites by PCR,then cloned into pEGFP-N2 and pEGFP-C1 vectors to obtain plasmids pEGFP-N2/MafA and pEGFP-C1/MafA.Human liver cancer cells(HepG-2) were transfected with formed plasmids by means of lipidosome.The MafA-EGFP fused protein was viewed directly with fluorensce microscope,and expression of MafA and insulin Ⅱ was detected by RT-PCR.Results:The mouse MafA gene was amplified through RT-PCR and successfully cloned into transfer vectors.The favorite gene sequence could be expressed and was completely consistent with that reported in genebank,but the insulin Ⅱ gene expression was not detected.Conclusion:The recombinant plasmids pEGFP-N2/MafA and pEGFP-C1/MafA were successfully constructed.But the insulin Ⅱgene was not expressed.