Cloning of Banana Bunchy Top Virus Chinese Zhangzhou Isolate DNA 4 and the Promoter Activity of Its Non_coding Region

Banana bunchy top virus Chinese Zhangzhou isolate (BBTV-ZZ) DNA 4 was amplified by PCR and cloned. Sequence analysis showed that BBTV-ZZ DNA 4 is 1 039 nucleotides (nts) in length and this virus could be one member of BBTV Asian group. Transcriptional initiation site A, which is at the 269 nucleotide, was preliminarily determined by using 5' RACE method. BBTV-ZZ DNA 4 non-coding region was sub-cloned by PCR and inserted into upstream of gfp : : gus plant expression vector pCAMBIA 1304 to construct recombinant plasmid pTA2. Agrobacterium tumefaciens harboring pTA2 was injected into leaves of the tobacco (Nicotiana tabacum L. cv. Xanthi NC) via Agrobacterium-infiltration procedure. Transient expressions of GUS and GFP were determined in injected leaves 3 - 5 d later. GUS activities of pTA2, pCAMBIA 1304 injected and non-injected tobacco leaves respectively were 1.007 0 pmol MU(.)mug(-1.)min(-1), 2.069 0 pmol MU(.)mug(-1.)min(-1) and 0.021 4 pmol MU(.)mug(-1.)min(-1). Indirect ELISA for GFP in 1 mg total protein from pTA2, pCAMBIA 1304 injected and non-injected leaves showed an A(490 nm) value of 89.577, 100.440 and 3.287, respectively. These results showed that the non-coding region of BBTV-ZZ DNA 4 has a promoter activity not only in the virus replication in monocot, but also in driving the expression of a foreign gene in dicot plants.

Complete genome sequence of two strawberry vein banding virus isolates from China

It was rarely reported about strawberry vein banding virus(SVBV)genome sequence in China and most countries worldwide.In this work,we determined the complete genome sequences of two SVBV isolates in China,designated SVBV-AH and SVBV-BJ,that were obtained from naturally infected strawberry samples from Anhui province and Beijing city of China,respectively.The complete genomes of SVBV-AH and SVBV-BJ were 7,862 nucleotides(nts)and 7,863 nts long,respectively,and both constituted with seven genes typical of the caulimoviruses.Alignment of complete nucleotide sequences showed that SVBV-AH and SVBV-BJ shared a significant nucleotide sequence identity of 97.7%of each other and had 85.7%and 86.0%sequence identity related to SVBV from the United States(SVBV-US),respectively.Phylogenetic trees,based on the alignment of complete nucleotide sequences and amino acid sequences of Coat Protein(CP),both showed that SVBV-AH and SVBV-BJ clustered into one branch with all the other SVBV isolates,and other species of caulimoviruses clustered into another tree branch.It illustrated that all the SVBV isolates had an extremely high relationship but had a distant relationship with other species of caulimoviruses.We further confirmed that SVBV-AH infectious clone could cause similar symptoms to SVBVinfected in strawberry under natural conditions.Taken together,our study provided valuable information to elucidate the origin and dissemination of SVBV Chinese isolates,meanwhile providing the necessary vector for studying the gene functions of strawberry.

Mechanism of anti-arterial thrombosis of Dahuangzhecong Fang screened by Ti-Al intermetallic compound porous material

The mechanism of antithrombotic of Dahuangzhechong Fang separated and purified by Ti-Al intermetallic compound porous material (TAICPM) was researched. Dahuangzhechong Fang, which was isolated and screened by TAICPM, was used to oral rats. At the end of study, their blood and thrombus were collected. The results show that TAICPM with the pore size of 1-5 μm can screen Dahuangzhechong Fang well. Dahuangzhechong Fang can increase 6-keto-PGF1α, lower content of TXD2 and platelet. Dahuangzhechong Fang has good effect to resist arterial thrombosis.