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 Flag (DYKDDDDK) expressing recombinant plasmids, pCMV-N-Flag-SND1-No1/2, which contain the coding sequence of human SND1-No1(from 1st AUG)or SND1-No2 (from 2nd AUG), and perform the cellular localization analysis of Flag-tagged SND1-No1/2 under stress condition to study the function of the two AUG in the SND1 containing stress granules formation. Methods The gene fragments of SND1-No1/2 were amplified by PCR from the whole SND1 transcript and inserted into pCMV-N-Flag expressing vector through BamHI/EcoRI double en-zyme digestion and T4 DNA Ligase connection. The recombinant pCMV-N-Flag-SND1-No1/2 plasmids were transfected in-to HeLa cells and the expression of Flag-SND1-No1/2 fusion proteins was examined by Western blotting assay. Immunofluo-rescence assay was performed to detect the co-localization of Flag-SND1-No1/2 with endogenous SND1 granule. Results The pCMV-N-Flag-SND1-No1/2 were sequenced and digested correctly by restriction single/double enzyme. The Flag-tagged SND1-No1/2 fusion proteins were also detected in transfected HeLa cell by Western blotting assay. Both of them showed the co-localization with endogenous SND1 granule. Conclusion The recombinant eukaryotic plasmids of pCMV-N-Flag-SND1-No1/2 were constructed successfully and expressed effectively. The depletion of 1st AUG failed to af-fect the formation of SND1 containing stress granules.
ABSTRACT
Background To explore the relationship between polymorphism of APOE gene in traumatic brain injury(TBI)patients suffering from traffic accident and the outcome of TBI.Methods TBI patients were randomly selected in this study with caxe-wntrol trial. The genotype of APOE allele was tested by a polymerase chain reaction-restriction fragment length polymorphism ( PCR-RFLP), and the association between different genotypes of APOE alleles and outcome of TBI patients, were analyed.Results In TBI group frequency of APOE ε2 allele was 0. 1010, and frequency of APOE ε2/ε3 was 0. 1596.Both of these results were significantly higher than that in normal people (APOE epsilon 2 was 0. 0050, APOE ε2/ε3 was 0. 0100) (P＜0.05). Frequency of APOE ε2 and APOE ε2/ε3 in TBI group who died was 0. 1970 and 0. 2727. These were significantly high compared to TBI patients who had good recovery.Conclusions APOE allele ε2 and APOE genotype ε2/ε3alleles indicate a poor prognosis of traumatic brain injury patients.