SEQUENCING AND FUNCTION ANALYSIS OF THE DEDUCED PROTEIN OF RICE DWARF VIRUS GENOME SEGMENT S4
水稻矮缩病毒第四号片段序列及编码蛋白的功能分析

The cDNA of Rice Dwarf Virus(RDV) Fujian isolate genome segment S4 was synthesized and amplified by RT-PCR. The PCR product was cloned and sequenced. The cloned fragment is 2217bp in length. It contains one large open reading frame and encodes a polypeptide with 727 amino acids in length. It shares 92.3% and 93.9% identity with RDV S4 of Japanese isolate in terms of nucleotide and amino acid sequences, respectively. Amino acid sequences similar to a zinc-finger and GTP-binding motifs were present in the deduced protein. Considerable amino acid sequence homology was detected between genome segment S4 of RDV and WTV. One of the sequences similar to the zinc-finger motif was present in a conserved region of the polypeptide of both viruses. However, the sequence similar to the GTP-binding motif was not present in the polypeptide encoded by genome segment 4 of WTV.