Tumor Supressor Genes

Question 1

Tumor Supressor genes first noted in….

Answer 1

Mullers classification of mutations

Question 2

Henry Harris evidence of tumor suppressor genes

Answer 2

he fused a normal and a cancer cell. THis would equal a normal cell UNLESS one of the alleles was lost

Question 3

knudson’s 2 hit hypothesis

Answer 3

used retinoblastomas to illustrate that famililar only need 1 hit but sporadic would need 2 hits because in famililar you already inherit a mutated gene copy

Question 4

mitosis events that promote a 2nd mutation

Answer 4

• nondysjuctions (failure for chromatins to separate) which means 1 cell gets 2 copies
  OR it happening again when there is only 1 chromatin and pressure to replicate again
• mutations in repair equipment and crossover or gene conversion

Question 5

gatekeepers (tumor supressors)

Answer 5

directly suppress cell proliferation

Question 6

caretakers

Answer 6

maintain genome

Question 7

RB1

Answer 7

gate keeper tumor supressor gene
- in mutant types they supress much more

Question 8

how does RB work to tumor supress

Answer 8

• it is a regulator of the S-phase entry of cell cycle
• need cyclin D kinase to activate it (from ERK cycle)
• then leads to Rb inactivity and therefore E2F activation which then PROMOTES CYCLIN E and S phase entry