The human papillomavirus type 11 E1/\E4 protein is not essential for viral genome amplification.
An abundant human papillomavirus (HPV) protein E1/\E4 is expressed late in the virus life cycle in the terminally differentiated layers of epithelia. The expression of E1/\E4 usually coincides with the onset of viral DNA amplification. However, the function of E1/\E4 in viral life cycle is not completely understood. To examine the role of E1/\E4 in the virus life cycle, we introduced a single nucleotide change in the HPV-11 genome to result in a truncation of E1/\E4 protein without affecting the E2 amino acid sequence. This mutated HPV-11 genome was introduced into a human foreskin keratinocyte cell line immortalized by the catalytic subunit of human telomerase, deficient in p16(INK4a) expression, and previously shown to support the HPV-11 life cycle when grown in organotypic raft culture. We have demonstrated that E1/\E4 is dispensable for HPV-11 viral DNA amplification in the late stages of the viral life cycle.
Fang
L
L
Department of Bioscience and Biotechnology, Drexel University, Stratton Hall Rm. 118, 3141 Chestnut Street, Philadelphia, PA 19104, USA.
Budgeon
L R
LR
Doorbar
J
J
Briggs
E R
ER
Howett
M K
MK