Expression Trend of Selected Ribosomal Protein Genes in Nasopharyngeal Carcinoma

Background: Ribosomal proteins are traditionally associated with protein biosynthesis until recent studies that implicated their extraribosomal functions in human diseases and cancers. Our previous studies using GeneFishingTM DEG method and microarray revealed underexpression of three ribosomal protein genes, RPS26, RPS27, and RPL32 in cancer of the nasopharynx. Herein, we investigated the expression pattern and nucleotide sequence integrity of these genes in nasopharyngeal carcinoma to further delineate their involvement in tumourigenesis. The relationship of expression level with clinicopathologic factors was also statistically studied. Methods: Quantitative Polymerase Chain Reaction was performed on nasopharyngeal carcinoma and their paired normal tissues. Expression and sequence of these three genes were analysed. Results: All three ribosomal protein genes showed no significant difference in transcript expressions and no association could be established with clinicopathologic factors studied. No nucleotide aberrancy was detected in the coding regions of these genes. Conclusion: There is no early evidence to substantiate possible involvement of RPS26, RPS27, and RPL32 genes in NPC tumourigenesis.

Cloning，Sequence Analysis and Expression in E.coli of the EP0 Gene of Pseudorabies Virus Ea Strain / 中国病毒学

The 1.23 kb DNA fragment encoding the early protein EP0 of pseudorabies virus (PRV) Ea strain was amplified by PCR technique and cloned into pBluescriptII sk+.Three sequencing plasmids containing the partial fragment of the EP0 gene were constructed and the sequences were obtained by Sanger's sequencing technique. Compared with PRV InFh strain, there were multipile site-mutations and a deleted-mutation in the EP0 gene of PRV strain Ea，and the diversity of amino acid residues also existed.Then, the EP0 gene was inserted into an expression vector, pET-28a, fused into the downstream of the 6ΧHis-Tag in frame, to yield the expression plasmid pETEP0. After induction by IPTG, a high expression of fusion protein was obtained, SDS-PAGE analysis and Western blotting showed that the fusion protein was 62kD and the protein was specific to antisera against PRV Ea strain. This indicated that the EP0 gene be expressed in BL21(DE3) and the expression products have immuno-genicity.