IP₃R clustering modulates calcium signals when co-localized.

Representative simulations of the particle-based model with the corresponding IP₃R distribution over space, the calcium trace and number of open IP₃R for weakly co-localized calcium sources (R_γ = 10) in the case of uniform distribution of the IP₃R (A) or strongly clustered IP₃R (B) are illustrated. The red crosses show peak locations from automatic detection. The impact of IP₃R cluster size η on calcium peak frequency (C) and on the amount of puffs (D) are shown for different values of the cluster size: from η = 1 (IP₃R are not clustered) to η = 50 (strong clustering). Data are presented as mean ± standard deviation over 20 simulations. Lines are guide for the eyes. Other parameters: D_Ca = 0.1 a.u, a₁ = 1 a.u, μ = 50 a.u.