In vitro expression of human cytomegalovirus UL148 RNA and prediction of its functional sites / 中华微生物学和免疫学杂志

Objective To express UL148 RNA of human cytomegalovirus (HCMV) clinical strains in vitro and to study its functions. Methods Urine of a newborn with HCMV infection was inocula-ted into human embryo lung cells. HCMV clinical strain was isolated and identified by multiplex PCR. UL148 gene was amplified and cloned into pGEM-T-Easy plasmid after double enzyme digestion. A recombi-nant plasmid was constructed and located at the downstream of the T7 promoter. The recombinant plasmid was identified by electrophoresis of the recombinant plasmid,PCR product and double enzyme product. Se-quencing analysis was used for final confirmation. UL148 was transcribed into RNA by 32P labeling. Post-translational modification sites were analyzed by bioinformatics method based on UL148 sequence characteris-tics. Results The clinical strain of HCMV was obtained in vitro. Electrophoresis and sequencing analysis confirmed the successful construction of the recombinant plasmid. UL148 RNA was transcribed in vitro by T7RNA polymerase. Post-translational modification sites showed that UL148 gene contained one cell adhe-sion sequence, one legume lectins beta-chain signature, two N-myristoylation sites, one casein kinase Ⅱphosphorylation site,seven protein kinase C phosphorylation sitse, one cAMP/cGMP-dependent protein ki-nase phosphorylation site, two N-glycosylation sites and one transmembrane region. Conclusion UL148 gene might encode a viral adhesion molecule involving in the signal transduction in host cells.

Effective inhibition of human cytomegalovirus UL148 gene expression by external guide sequences in vitro / 中华实验和临床病毒学杂志

Objective@#To investigate the UL148 gene function of human cytomegalovirus (HCMV) low passage clinic isolate and new strategies for anti-HCMV treatment, the DNA-based external guide sequences (EGSs) were designed to inhibit UL148 RNA expression.@*Methods@#UL148 RNA secondary structure was analyzed by RNA structure technique, an appropriate region was chosen for DNA-based EGS57 synthesis, targeted the UL148 RNA. The M1RNA and UL148 RNA were generated by PCR for transcription in vitro. The UL148 RNA and M1RNA were transcribed in vitro under the function of T7 RNA polymerase. The UL148 was labelled by 32P. The cleavage reactions were carried out by mixing up EGS, M1RNA with UL148 RNA for 1 h. The products were separated by urea denaturing polyacrylamide gel electrophoresis and detected with Typhoon Phosphor Imager.@*Results@#UL148 RNA ranged from 58 to 72 sites was the binding position, and 57 was a cleavage site. EGS57 was designed and synthesized. EGS57 was combined with UL148 RNA to form the natural substrate of M1RNA. UL148 RNA and M1RNA were synthesized through T7 RNA polymerase catalyzing, and the products were conformed. After cleaving reactions, DNA-based EGS57 was shown to be able to cleave UL148 RNA efficiently in vitro by a complex with M1RNA.@*Conclusions@#UL148 RNA was cleaved efficiently by EGS57, and the cleaving site was conformed as expectation. It will provide the gene silent tool effectively for further study the function of UL148 gene.