The Capsid Precursor Protein of Astrovirus VA1 Is Proteolytically Processed Intracellularly
Catalina Aguilera-Flores, Tomás López, Fernando Z. Zamudio, Carlos Sandoval-Jaime, Edmundo I. Pérez, Susana López, Rebecca M. DuBois, Carlos F. Arias
Abstract
Human astrovirus VA1 has been associated with neurological disease in immunocompromised patients. Its recent propagation in cell culture has facilitated the study of its biology. In this work, we show that despite the ability of this virus to grow in the absence of trypsin, a marked feature of human classical astroviruses, the capsid precursor protein of astrovirus VA1 is cleaved intracellularly to yield the mature infectious particles, formed by two polypeptides, VP33 that constitutes the core domain of the virus particle, and VP38 that forms the spike of the virus. These studies provide a platform to advance our knowledge on astrovirus VA1 cell entry and replication.