新城疫（ND）目前仍然是危害我国乃至世界养禽业的重要疫病。随着基因Ⅶ型新城疫病毒（NDV）毒株的流行，导致接种疫苗后的鸡群发生非典型ND。对于NDV的进一步研究十分必要。NDV M蛋白在病毒粒子出芽中起关键作用，但具体的分子机制尚不清楚。我们前期研究发现NDV M蛋白具有两种晚期结构域基序（L-domain），有报道显示病毒L-domain能够劫持宿主转运必需内体分选复合物(ESCRT)增强出芽能力。本研究将以NDV基因Ⅶ型aSG10弱毒株为材料，开展M蛋白L-domain影响NDV病毒粒子出芽的分子机制研究。利用反向遗传构建NDV L-domain突变的嵌合病毒，研究M蛋白L-domain对病毒粒子出芽效率和体内外复制的影响，以期揭示NDV利用宿主ESCRT系统来帮助其病毒粒子出芽的分子机制，为阐明NDV的病毒粒子出芽和病毒复制机制提供科学依据，为有效的控制病毒感染和传播提供理论依据。

Newcastle disease (ND) is still an important disease in poultry industry in China and worldwide. Genotype Ⅶ NDV causes the vaccinated chickens atypical ND. It is necessary to further study NDV. NDV M protein plays a key role in the budding of virion, but the exact molecular mechanism is not clear. Our previous study found that NDV M protein has at least two late-domain (L-domain) motifs. It has been reported that the L-domain of the virus can hijack the transport the required endosomal sorting complex (ESCRT) of the host to enhance the ability to bud. In this study, attenuated genotype Ⅶ strain aSG10 of NDV will be used to study the molecular mechanism of the L-domain of NDV M protein affects its budding. Using reverse genetic technology, chimeric viruses mutated by the M protein L-domain of NDV aSG10 strain will be constructed to study the effect of the L-domain motif on the budding efficiency and viral replication in vivo and in vitro. These results will reveal the molecular mechanism by which NDV uses the host ESCRT system to help its virion budding, and elucidate scientific basis for the mechanism of NDV virus replication, and provide a theoretical basis for the effective control of virus infection and transmission.