This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Krajcsi, P Articles by Wold, W S Search for Related Content PubMed PubMed Citation Articles by Krajcsi, P Articles by Wold, W S

 Previous Article  |  Next Article 

J Virol. 1992 March; 66(3): 1665-1673

The adenovirus E3 14.5-kilodalton protein, which is required for down-regulation of the epidermal growth factor receptor and prevention of tumor necrosis factor cytolysis, is an integral membrane protein oriented with its C terminus in the cytoplasm.

Institute for Molecular Virology, St. Louis University School of Medicine, Missouri 63110.

ABSTRACT

We previously reported that the adenovirus type 5 E3 14.5-kilodalton protein (14.5K) forms a complex with E3 10.4K and that both proteins are required to down-regulate the epidermal growth factor receptor in adenovirus-infected human cells. Both proteins are also required to prevent cytolysis by tumor necrosis factor of most mouse cell lines infected by adenovirus mutants that lack E3 14.7K. The E3 14.5K amino acid sequence suggests that 14.5K is an integral membrane protein with an N-terminal signal sequence for membrane insertion. Here we show that 14.5K was found exclusively in cytoplasmic membrane fractions. Radiochemical sequencing of 14.5K indicated that the N-terminal signal sequence is cleaved predominantly between Cys-18 and Ser-19. With a mutant that does not express 10.4K, cleavage occurs predominantly between Phe-17 and Cys-18, indicating that the presence or absence of 10.4K affects the signal cleavage site. 14.5K was extracted into the detergent phase with Triton X-114, it remained associated with membranes after extraction with Na2CO3 at pH 11.5, and it was partially protected by membranes from proteinase K digestion; these observations indicate that 14.5K is an integral membrane protein. Proteinase K digestion followed by immunoprecipitation with antipeptide antisera directed against the N or C terminus of mature 14.5K indicated that 14.5K is oriented in the membrane with its N terminus in the lumen and its C terminus in the cytoplasm. Thus, 14.5K is a type I bitopic membrane protein. Previous studies indicated that 10.4K is also an integral membrane protein oriented with its C terminus in the cytoplasm. Altogether, these findings suggest that cytoplasmic membranes are the site of action when 10.4K and 14.5K down-regulate the epidermal growth factor receptor and prevent tumor necrosis factor cytolysis.

This article has been cited by other articles:

• Lichtenstein, D. L., Doronin, K., Toth, K., Kuppuswamy, M., Wold, W. S. M., Tollefson, A. E. (2004). Adenovirus E3-6.7K Protein Is Required in Conjunction with the E3-RID Protein Complex for the Internalization and Degradation of TRAIL Receptor 2. J. Virol. 78: 12297-12307 [Abstract] [Full Text]  
• Zanardi, T. A., Yei, S., Lichtenstein, D. L., Tollefson, A. E., Wold, W. S. M. (2003). Distinct Domains in the Adenovirus E3 RID{alpha} Protein Are Required for Degradation of Fas and the Epidermal Growth Factor Receptor. J. Virol. 77: 11685-11696 [Abstract] [Full Text]  
• Lichtenstein, D. L., Krajcsi, P., Esteban, D. J., Tollefson, A. E., Wold, W. S. M. (2002). Adenovirus RID{beta} Subunit Contains a Tyrosine Residue That Is Critical for RID-Mediated Receptor Internalization and Inhibition of Fas- and TRAIL-Induced Apoptosis. J. Virol. 76: 11329-11342 [Abstract] [Full Text]  
• Benihoud, K., Saggio, I., Opolon, P., Salone, B., Amiot, F., Connault, E., Chianale, C., Dautry, F., Yeh, P., Perricaudet, M. (1998). Efficient, Repeated Adenovirus-Mediated Gene Transfer in Mice Lacking both Tumor Necrosis Factor Alpha and Lymphotoxin alpha. J. Virol. 72: 9514-9525 [Abstract] [Full Text]