Functional genomics of Cherry leaf roll virus (CLRV) and molecular analyses of Finnish virus variants

樱桃卷叶病毒（Cherry leaf roll virus， CLRV）是Comoviridae科C Nepovirus的一个亚群，具有两部分ss (+)RNA基因组，我们最近对其进行了完全测序。除病毒外壳蛋白外，尚未实现clrv编码的基因产物的功能表征或编码的多蛋白前体（RNA1编码P1， RNA2编码P2）被假定的病毒蛋白酶（Pro）加工，因此是本提案的主要研究课题。此外，clrv编码的基因与数据库中可用的任何特征蛋白没有相似性，目的是对其进行功能分析，以促进我们对新病毒基因功能的一般认识。该病毒感染许多木本植物和几种草本植物，广泛分布于温带地区。拟议的研究将包括芬兰CLRV变异的遗传和血清学特征，这可能与最近在全国范围内损害几种重要桦树物种的流行病有关。同时，将分析感染芬兰桦树的病毒种群结构，因为初步调查显示来自芬兰的CLRV代表非典型序列变异。这将有助于将分子特征与血清学数据和在芬兰观察到的疾病症状联系起来，这可能有助于对严重疾病情况进行实质性评估。

Cherry leaf roll virus (CLRV) is a subgroup C Nepovirus (family Comoviridae) with a bipartite ss (+)RNA genome, which we have recently completely sequenced. Apart from the viral coat protein, functional characterization of CLRV-encoded gene products or processing of the encoded polyprotein precursors (RNA1 encoded P1 and RNA2 encoded P2) by the putative viral proteinase (Pro) has never been achieved and is therefore a main research topic of this proposal. Furthermore, functional analyses of CLRV-encoded genes which exhibit no similarity to any characterized protein available in the databases are intended, in order to contribute to our general knowledge of nepovirus´ gene functions. The virus infects many woody and several herbaceous species and is widespread in temperate regions. The proposed study will include genetic and serological characterization of Finnish CLRV variants, which could be associated with a recent epidemic impairing several important birch species all over the country. In parallel, population structure of the virus infecting Finnish birch trees will be analyzed, because initial investigations showed that CLRV from Finnish origins represent atypical sequence variants. This will facilitate the correlation of the molecular traits with serological data and the disease symptoms observed in Finland which may contribute to the substantial evaluation of the severe disease situation.