Yang Zhi-rong

Cloning and Sequence Analysis of the Gene Encoding (6-4)photolyase from Dunaliella salina

DNA photolyase can repair UV-induced DNA damage in a light-dependent manner. A cDNA of (6-4)photolyase from Dunaliella salina (GenBank accession number: AY845324) was cloned, sequenced and its amino acid sequence was deduced. The derived amino acid sequence showed high homology with other (6-4)photolyases and a predicted 3D model was constructed by homology modeling.

Effect of siRNA on HSV-1 plaque formation and relative expression levels of UL39 mRNA

RNA interference (RNAi) is a process by which introduced small interfering RNA (siRNA) can cause the specific degradation of mRNA with identical sequences. In this study, we applied siRNAs targeting the UL39 gene of human herpes simplex virus type 1 (HSV-1), which encodes the large subunit of ribonucleotide reductase, ICP6. Using an ICP6 expression reporter plasmid and an in vitro model of infection, we showed that synthetic siRNA silenced effectively and specifically UL39 mRNA expression and inhibited HSV-1 replication. Our work offers new possibilities for RNAi as a genetic tool for inhibition of HSV-1 replication.

Cloning and expression studies of the Dunaliella salina UDP-glucose dehydrogenase cDNA

The enzyme UDP-glucose dehydrogenase (EC 1.1.1.22) converts UDP-glucose to UDP-glucuronate. Plant UDP-glucose dehydrogenase (UGDH) is an important enzyme in the formation of hemicellulose and pectin, the components of primary cell walls. A cDNA, named DsUGDH, (GeneBank accession number: AY795899) corresponding to UGDH was cloned by RT-PCR approach from Dunaliella salina. The cDNA is 1941-bp long and has an open reading frame encoded a protein of 483 amino acids with a calculated molecular weight of 53 kDa. The derived amino acids sequence shows high homology with reported plants UGDHs, and has highly conserved amino acids motifs believed to be NAD binding site and catalytic site. Although UDP-glucose dehydrogenase is a comparatively well characterized enzyme, the cloning and characterization of the green alga Dunaliella salina UDP-glucose dehydrogenase gene is very important to understand the salt tolerance mechanism of Dunaliella salina. Northern analyses indicate that NaCl can induce the expression the DsUGDH.