Human papillomavirus type 16 E5 protein localizes to the Golgi apparatus but does not grossly affect cellular glycosylation.

The E5 protein of papillomaviruses is a strongly hydrophobic membrane protein that can associate with the 16 kDa protein subunit of the vacuolar proton ATPase in endosomes and the Golgi apparatus resulting in raise of intraorganelle pH. We demonstrate that E5 of human papillomavirus type 16 (HPV16) when transfected into human keratinocytes localizes to the Golgi. Using FACS analysis and western blotting with a variety of lectins as well as analysing the sialylation status of a specific cell surface glycoprotein CD95 (APO-1/Fas), we show that HPV16 E5 does not grossly affect cellular glycosylation, a main Golgi function.