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Wei Jin

Publications and source records attributed to Wei Jin.

75 records · Page 5Linked to original sources

Inactivation Analysis of HcNPV Cysteine Protease Gene and Chitinase Gene.

The fragment of Hyphantria cunea nuclear polyhedrosis virus (HcNPV), which contains cysteine protease gene(CP) and chitinase gene (ChiA),was inserted into plasmid PCRII to construct transfer vector pHcCVdel. Recombinant transfer vector pHcCvpolh was constructed by inserting the fragment of HcNPV polyhedrin gene (polh) into the EcoRI site of the pHcCVdel. By contransfection of the pHcCvpolh and HcNPV-PTTH(+) DNA, which contained Bombyx mori prothoracicotropic hormone gene (PTTH) into SPIM cells, the region from +76 downstream of ChiA gene initiation codon to +20 downstream of CP gene initiation codon was substituted by the polh gene, and the recombinant virus HcNPVpolh(+)CP(-)ChiA(-)PTTH(+) was produced. The recombinant virus, in which CP gene and ChiA gene were inactive, could express PTTH gene and form polyhedra. SPIM cells infected with the recombinant virus revealed that CP and ChiA gene were not essential for viral replication and had no significant effect on polyhedron formation, but the infected cells survived 2 days more than those infected with HcNPV and HcNPVPTTH(+). Therefore, the expression time of foreign gene may be prolonged when CP gene and ChiA gene were inactivated.

Journal Article↗

Nucleotide Sequence Analysis of the HcNPV Cysteine Protease Gene.

The cysteine protease (CP) gene of Hyphantria cunea nuclear polyhedrosis virus (HcNPV) has been located at the Hind III--3.5 kb fragment. The nucleotide sequence has been determined. The results indicated that its open reading frame of 975 nt encoded the protein of 324 amino acids. The baculovirus late gene promoter TAAG motif was identified at -24 nt upstream from the start codon ATG; The typical poly (A) signal sequence AATAAA was detected at 33 nt downstream from the stop codon TAA. The HcNPV CP exhibited 81%, 76% and 76% homology at the nucleotide level, and 85%, 78%, 76% homology at the amino acid level to that of CfNPV (Choristoneura fumiferana nuclear polyhedrosis virus), AcNPV (Autographa californica nuclear polyhedrosis virus) and BmNPV (Bombyx mori nuclear polyhedrosis virus), respectively. HcNPV CP was a memeber of the papain superfamily and showed high homology to other cysteine protease, particularly, to those from Trypanosoma brucei and Dictyostelium discoideumwith 31.8%, 34.5% identity at the amino acid level, respectively. Of 36 residues conserved among cathepsins B, H, L and S and papain, 32 were identical in HcNPV CP. The ERFNIN interspersed amino acid motif was found within the propeptide region of the HcNPV CP. The Gly-Cys-Asn-Gly-Gly motif conserved among all cysteine protease was also detected in HcNPV CP.

Journal Article↗

Uniform head in horizontal and vertical wells.

The steady-state head within a fully penetrating well may be estimated by evaluating the Thiem equation at the radius of the well. A method is presented here to extend results from the Thiem equation to horizontal wells and to partially penetrating wells. The particular model used in this investigation is based upon the analytic element method; it accurately reproduces a boundary condition of uniform head along the cylindrical surface at the perforated face of the well. This model is exercised over a representative range of parameters including the well's length, radius, and pumping rate, and the aquifer's hydraulic conductivity and thickness. Results are presented in a set of figures and tables that compare the well's drawdown to the drawdown that would have been obtained using the Thiem solution with the same pumping rate and radius. A methodology is presented to estimate the head within a horizontal or partially penetrating well by adding a correction term to results that can be readily obtained from computer models of vertical fully penetrating wells. This approach may also be used to contrast the differences in head between horizontal and vertical wells of various lengths, radii, and placement elevations.

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