Author: Sofia Korneva
This repository presents the Ultra-Slow Component Model (USC-Model) — an ODE-based quantitative model describing DNA double-strand break (DSB) repair kinetics and ATM/γH2AX signaling in human stem cells.
The model extends the baseline Bi-Component Repair Model (BCRM) by introducing an ultraslow fraction of complex DNA damage that reproduces the persistent γH2AX / pATM “tail” observed at 24 h.
The ultraslow pool corresponds to damage that persists for tens of hours:
Clustered / dirty-end DSBs requiring long enzymatic processing (PNKP, Artemis).
Heterochromatin-associated breaks (H3K9me3 / HP1α) repairing via delayed HR.
Stable ATM microdomains around unrepaired DSBs or telomeres.
Thus Model C⁺ provides a mechanistic—not phenomenological—explanation of long-lived DNA damage signaling.