Formation of periodic pigment spots by the reaction-diffusion mechanism

Ding, B.; Patterson, E. L.; Holalu, S.; Li, J.; Johnson, G. A.; Stanley, L. E.; Greenlee, A. B.; Peng, F.; Bradshaw, H. D.; Blackman, B. K.; Yuan, Y.-W.

doi:10.1101/403600

bioRxiv · 10.1101/403600

Formation of periodic pigment spots by the reaction-diffusion mechanism

Ding, B.·Patterson, E. L.·Holalu, S.·Li, J.·Johnson, G. A.·Stanley, L. E.·Greenlee, A. B.·Peng, F.·Bradshaw, H. D.·Blackman, B. K.·Yuan, Y.-W.

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Abstract

Many organisms exhibit visually striking spotted or striped pigmentation patterns. Turings reaction-diffusion model postulates that such periodic pigmentation patterns form when a local autocatalytic feedback loop and a long-range inhibitory feedback loop interact. At its simplest, this network only requires one self-activating activator that also activates a repressor, which inhibits the activator and diffuses to neighboring cells. However, the molecular activators and repressors fully fitting this versatile model remain elusive. Here, we characterize an R2R3-MYB activator and an R3-MYB repressor in monkeyflowers that correspond to Turings model and explain how periodic anthocyanin spots form. Notably, disrupting this pattern impacts pollinator visitation. Thus, subtle changes in simple reaction-diffusion networks are likely essential contributors to the evolution of the remarkable diversity of periodic pigmentation patterns in flowers.

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Ding, B., Patterson, E. L., Holalu, S., Li, J., Johnson, G. A., Stanley, L. E., Greenlee, A. B., Peng, F., Bradshaw, H. D., Blackman, B. K., Yuan, Y.-W.. 2018-08-30. Formation of periodic pigment spots by the reaction-diffusion mechanism. https://doi.org/10.1101/403600

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