刺茄中分离的中国番茄黄化曲叶病毒及伴随的卫星DNA分子的全基因组结构

 从云南砚山刺茄(Solanum aculeatissimum)上分离到病毒分离物Y322,全序列测定表明,Y322 DNA-A全长2 730个核苷酸,共编码6个ORF。基因组比较发现,Y322 DNA-A与中国番茄黄化曲叶病毒(TYLCCNV)各分离物的同源性最高(88.3%~99.2%),而与其它双生病毒的同源性均在79.6%以下,表明Y322是TYLCCNV的一个分离物。利用DNAβ的特异性引物在Y322中扩增到DNAβ分子(Y322 β),序列分析表明,其全长1 331个核苷酸,与TYLCCNV伴随的DNAβ的同源性最高,达75.1%~93.1%,而与已报道的其它种类的DNAβ的同源性均低于55.4%。这是首次在刺茄中检测到中国番茄黄化曲叶病毒。

Genomic characterization of DNA-A and associated satellite DNA molecule of an isolate of Tomato yellow leaf curl China virus in Solanum aculeatissimum

The virus isolate Y322 was obtained from Solanum aculeatissimum showing leaf curl and enation symptoms in Yanshan, Yunnan Province. Complete nucleotide sequence of the DNA-A like molecule of Y322 was determined to be 2 730 nucleotides. Y322 DNA-A was most closely related to isolates of Tomato yellow leaf curl China virus (TYLCCNV) with 88.3%-99.2% nucleotide sequence identities, while less than 79.6% nucleotide sequence identities were found in comparisons with other begomoviruses. Therefore, Y322 was taxonomically considered as an isolate of TYLCCNV. Further studies showed that Y322 was associated with a DNA β molecule. The DNA β of Y322 contained 1 331 nucleotides having the highest nucleotide sequence identity (75.1%-93.1%) with DNA β associated with TYLCCNV, while less than 55.4% nucleo-tide sequence identities were found in comparisons with other DNA β molecules. This is the first report of TYLCCNV in S. aculeatissimum.