Papillomaviruses Flashcards
What type of genome do papillomaviruses have
dsDNA viruses
Describe the structure of papillomaviruses
55nm in diameter
Non-enveloped
72 pentameric capsomere units
Size of papillomavirus genome
8000bp
Where do papillomaviruses replicate
The nucleus
Splicing of it allows more gene products to be produced
How many genes does the genome enode
6 early genes
2 late genes
What is the role of E3 and E8
They are putative genes that are only expressed in a few papillomaviruses
Describe the genes that are expressed in the lower, mid and upper layers of the epithelium
Lower - E6 and E7
Mid - E4 and E5
Upper - L1 and L2
How many types of HPV disease are there
130
30 cause warts
15 cause cervical cancer
How many cases of cervical cancer are there annually
530,000 –> 3rd most common female cancer
Where does the majority of cervical cancer occur
85% in developing countries
What % of young women and older woman are infected
About 33% of normal young woman are infected
Only 3% of the over 50s are infected
What % of women infected with HPV16 will develop cervical cancer within 45 years of infection
7%
Within what time frame have most people cleared HPV infection
within 3 years
What evidence suggest the E5 protein may contribute to carcinogenesis
In transgenic mice models E5 can produce epithelial proliferation
In oestragen treated mice models E5 was sufficient to cause cervical cancers
By what mechanisms might E5 contribute to carcinogenesis
May alter the activity of EGFR
May reduce the surfcace levels of MHC Class I proteins, modulate the MAPK pathway and alter calveolin levels
