The Complete Nucleotide Sequences And Their Organizations Of The Genomes Of Two Chinese Virus Isolates And Nucleic Acid Spot Hybridization Applied With Digoxigenin-labelled CDNA Probes To Detect PMMoV

Barley yellow dwarf virus PAV-CN is a Chinese isolate and serologically related with BYDV-PAV, but they are not identical. Both are transmitted by Macrosiphum avenae ,but PAV is also transmitted by Schizaphis graminum. PMMoV-CN is a chines isolates of pepper mild mottle virus. The complete nucleotide sequences of the genomic RNA of BYDV PAV-CN and PMMoV-CN were determined ,and compared with other relative viruses.The nucleotide sequence of genome of BYDV PAV-CN was overlapped by the fragments obtained through RT-PCR The primers used in RT-PCR were designed according to the conserved sequence among letuoviruses and reported sequences of CN-PAV. Sequences of terminal region of genome were identified by 5'RACE and 3' anchored PCR. The complet genomic sequences of PAV-CN have been identified. And its lenth is 5652nts, which is in good agreement with that of all other BYDVs. Comparison of PAV-CN and other isolates of BYDVs show that PAV-CN is special in BYDVs. Although PAV-CN is conserved with BYDV-PAVs on its genomic organization, gene expression and squences necessary for gene expression and regulation. The genome of PAV-CN has its special factors. Firstly, the whole genome identity between PAV-CN and PAV-129 is only 80.2%, which is the highest identities among BYDVs; And that of the other PAVs is less than 80.0%. The 5'NCR of PAV-CN share the highest nuleotide identities with GAV. Their nucleotide identity can reach 97.9%, while those of BYDV-PAVs only about 92.9%; Except this regions, the PAV-129 shares the highest identities with PAV-CN in the other regions. Like PAV-129, ORFs 1 and 2 of PAV-CN are more divergent from other BYDV-PAVs. Secondly, the CP gene of PAV-CN is very special. Its deduced amino acid identities with the other BYDV-PAVs is only 71.0%-74.0%, while deduced amino acid identities of CP gene among other PAVs is higher than 86.5%. Thirdly, the ORF5, which is necessary for aphid transmission, is varible in PAV-CN and the mutation regions is similar with GAV. Finally, the four NCRs also share low identities with BYDV-PAVs, though PAV-CN has the conserved regions with them.The nucleotide sequence of genome of PMMoV-CN was overlapped by the fragments obtained through RT-PCR The primers used in RT-PCR were designed according to the conserved sequence among PMMoV. Sequences of terminal regions of genome were identified by 5'RACE and 3' anchored PCR. Based on the sequencing data, the gonome of PMMoV-CN consisted of 6356 nucleotides (nt). It contained four open reading frames...