Telomere Dynamics

Telomerase extension, t-loop protection, and the Hayflick limit
Simulation Controls
Cell State
Divisions: 0
Telomere length: 10000 bp
Length:
Telomerase: OFF
State: Healthy
Hayflick limit: ~50 divisions
Biology
Telomeres: TTAGGG repeats
End-replication problem:
 lagging strand loses ~50-200bp
t-loop: G-overhang invades
 duplex → protects end
Shelterin: TRF1/2, POT1,
 RAP1, TIN2, TPP1
<5kb → p53/RB senescence
Telomerase: TERT + TERC