ATM and ATR Activation Through Crosstalk Between DNA Damage Response Pathways.

Area of Science:

• Cellular biology
• Cancer research
• Mathematical modeling

Background:

• Cellular self-regulation fails in cancer, leading to uncontrolled growth.
• Damage response pathways involve repair, cell cycle arrest, or apoptosis.
• Reconciling diverse damage signals is a key cellular challenge.

Purpose of the Study:

• To develop the first mathematical model of crosstalk between ATM and ATR signaling pathways.
• To simulate the pro-apoptotic signal induced by [Formula: see text] and UV radiation.
• To investigate the contributions of different crosstalk mechanisms to ATM/ATR signaling.

Main Methods:

• Constructed a mathematical model incorporating three modes of ATM/ATR crosstalk.
• Calibrated the model against 21 experimental claims regarding ATM/ATR crosstalk.
• Systematically altered the model to assess the impact of individual crosstalk processes.

Main Results:

• The model successfully simulates ATM/ATR crosstalk in response to [Formula: see text] and UV radiation.
• Positive feedback, mutual upregulation, and lesion topology changes were identified as key crosstalk modes.
• Analysis revealed the specific contributions and violations associated with each crosstalk mechanism.

Conclusions:

• Pro-apoptotic signaling is a holistic cellular effort, not solely dependent on a single kinase.
• Mathematical modeling provides a powerful tool for dissecting complex signaling networks.
• Understanding ATM/ATR crosstalk is crucial for cancer therapy development.