Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí sinh học đề tài : A conditional-lethal vaccinia virus mutant demonstrates that the I7L gene product is required for virion morphogenesis | Virology Journal BioMed Central Short report Open Access A conditional-lethal vaccinia virus mutant demonstrates that the I7L gene product is required for virion morphogenesis Chelsea M Byrd1 and Dennis E Hruby 1 2 Address 1Molecular and Cellular Biology Program Oregon State University 220 Nash Hall Corvallis Oregon 97331 USA and 2Department of Microbiology Oregon State University 220 Nash Hall Corvallis Oregon 97331 USA Email Chelsea M Byrd - cbyrd@ Dennis E Hruby - dhruby@ Corresponding author Published 08 February 2005 Received 07 December 2004 Accepted 08 February 2005 Virology Journal 2005 2 4 doi 1743-422X-2-4 This article is available from http content 2 1 4 2005 Byrd and Hruby licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract A conditional-lethal recombinant virus was constructed in which the expression of the vaccinia virus I7L gene is under the control of the tetracycline operator repressor system. In the absence of I7L expression processing of the major VV core proteins is inhibited and electron microscopy reveals defects in virion morphogenesis subsequent to the formation of immature virion particles but prior to core condensation. Plasmid-borne I7L is capable of rescuing the growth of this virus and rescue is optimal when the I7L gene is expressed using the authentic I7L promoter. Taken together these data suggest that correct temporal expression of the VV I7L cysteine proteinase is required for core protein maturation virion assembly and production of infectious progeny. Proteolytic cleavage of precursor proteins is an essential process in the life cycle of many viruses including vaccinia virus VV . The cysteine proteinase encoded by the VV I7L gene was .
