Instituto Universitario de Biotecnología de Asturias, Departamento de Bioquímica y Biología Molecular, Edificio Santiago Gascón, Campus El Cristo, Universidad de Oviedo, 33006 Oviedo, España.
Virol J. 2010 Feb 26;7:49. doi: 10.1186/1743-422X-7-49.
Myxoma virus (MV) has been endemic in Europe since shortly after its deliberate release in France in 1952. While the emergence of more resistant hosts and more transmissible and attenuated virus is well documented, there have been relatively few studies focused on the sequence changes incurred by the virus as it has adapted to its new host. In order to identify regions of variability within the MV genome to be used for phylogenetic studies and to try to investigate causes of MV strain attenuation we have molecularly characterised nine strains of MV isolated in Spain between the years 1992 and 1995 from wide ranging geographic locations and which had been previously graded for virulence by experimental infection of rabbits.
The findings reported here show the analysis of 16 genomic regions accounting for approximately 10% of the viral genomes. Of the 20 genes analysed 5 (M034L, M069L, M071L, M130R and M135R) were identical in all strains and 1 (M122R) contained only a single point mutation in an individual strain. Four genes (M002L/R, M009L, M036L and M017L) showed insertions or deletions that led to disruption of the ORFs.
The findings presented here provide valuable tools for strain differentiation and phylogenetic studies of MV isolates and some clues as to the reasons for virus attenuation in the field.
自从 1952 年在法国故意释放以来，粘液瘤病毒 (MV) 在欧洲一直流行。虽然已经有大量文献记录了更具抗性的宿主和更具传染性和减毒的病毒的出现，但很少有研究集中在病毒适应新宿主时所发生的序列变化上。为了确定 MV 基因组中发生变异的区域，以便用于系统发育研究，并试图调查 MV 株减毒的原因，我们对 1992 年至 1995 年间在西班牙从广泛地理区域分离的 9 株 MV 进行了分子特征分析，这些病毒株先前已通过实验感染兔子进行了毒力分级。
本报告中的发现显示了对大约占病毒基因组 10%的 16 个基因组区域的分析。在分析的 20 个基因中，有 5 个（M034L、M069L、M071L、M130R 和 M135R）在所有菌株中完全相同，而 1 个（M122R）在单个菌株中只含有一个点突变。有 4 个基因（M002L/R、M009L、M036L 和 M017L）显示插入或缺失，导致 ORF 中断。
本研究中的发现为 MV 分离株的株系分化和系统发育研究提供了有价值的工具，并为野外病毒减毒的原因提供了一些线索。
