Viruses

Question 1

ROus sarcoma virus example…

Answer 1

Retrovirus that contains the src gene, src is a protein tyrosine kinase. INfects chickens. There is a copy in the host c-src which is used in signalling from the egf receptor to increase cell proliferation. v-src is a slightly different isoform that has no inhibitory site so cant be inactivated… always active so aways signalling to proliferate…sarcoma formation. Innhibited by dasatinib (ant cancer drug for only src tumours)

Question 2

Avian leukosis virus

Answer 2

Retrovirus. Contains no addition genes for proteins to be made, but it inserts a dna sequence in before the c-myc gene in b cells. this causes over expression of the c-myc genes, leading to rapid cell cylcing and thus rapid cell proliferation. Leads to tumour formation.

Question 3

Xentrophic murine related virus like virus

Answer 3

Isolated in prostate cancer, but later shown to be the causative agent in chronic fatigue syndrome. Not acually a virus, it was formed fue to contamination. acually a hybrid virus from 2 different retorviruses

Question 4

Lentiviral vectors

Answer 4

Retroviruses with the infectious genes removed so they are no longer a risk to the host cells. These are highly infectious so are used to create higly efficient trans fection vehicles. … insert our GOI into the packaging genes of the virus. Infect a HEK293 cell line which produced virus like particles. COllect these and transfect our organism of choice.

Question 5

SYmptoms of HPV1

Answer 5

Plantatr warts on feeet (varuca)

Question 6

HPV 2 + 4

Answer 6

Common warts

Question 7

HPV 7

Answer 7

Warts on hands, butchers warts

Question 8

HPV 6 + 11

Answer 8

Warts in the genital tract

Question 9

HPV 16, 18, 31

Answer 9

Cerival an =d head and neck cancers

Question 10

EBV

Answer 10

cause chromosomal translocations leading to burkitt’s lymphona. Gene from chromosome 14 IgH could move nadjacent to the c myc gene so when the IgH is a=expressed (often as it produces antibodides) the c-myc gene is also expressed and leads to increase cell cycle rate and proliferation

Question 11

Whic 2 proteins are used in HPV to cause cancers

Answer 11

E6 and E7

Question 12

What does e7 bind

Answer 12

Rb. This sequesters the E2F TF needed to promotte the s phase of the cell cycle. E7 binds to Rb and the complex enters the proteolytic pathway. If less rb less e2f sequestered so more to promote cell cye, increased cell proliferation

Question 13

What does e6 bind to

Answer 13

e6 binds to p53 tumour supressor gene. This sense dna damage and cellular stress and so can halt the cell cycle of cause apoptisis depending on the situation. By having more cell cycling and aberrant dna gene exression tuours can form

Question 14

What is used in making a HPV virus

Answer 14

L1 proteins. These spontaneously form virus like particles that can induce an immune response.