The Dynamics of Auxin Signaling and Response During Root Gravitropism
The seminar takes place on March 25th at 3 PM in the KFR/213 room, Viničná 5, 2nd floor. Guests are welcome!
Mgr. Matyáš Fendrych, Ph.D. (Institute of Experimental Botany, CAS - Laboratory of Plant Morphodynamics)
contact email: fendrych.m@ueb.cas.cz
Join us online: meet.google.com/qhf-etyu-sna
Roots navigate in the darkness of soil along the gravity vector. The primary root of Arabidopsis thaliana responds to the change of gravity direction with a remarkable speed. The ability to respond quickly might be important during navigation through heterogeneous soil environments. Root gravitropism relies on the interplay of intercellular auxin transport, auxin perception and auxin response that manifests as inhibition of cellular elongation. The speed of gravitropic response of Arabidopsis roots led to the discovery of a cytoplasmic rapid auxin response module that operates in parallel to the long-studied TIR1/AFB nuclear auxin response signaling.
I will show how the rapid and nuclear auxin response pathways interact during the course of the gravitropic response. The rapid response pathway depends on the auxin receptor AFB1 that resides in the cytoplasm. I will present our current understanding of the molecular nature of this pathway. Further, I will focus on cellular auxin responses that are required for the execution of root gravitropic bending, namely changes in ion fluxes, increase of cell wall pH and transcriptomic changes triggered by auxin. I will show how the auxin signaling systems coordinately regulate these processes and I will present our search for genes that are executers of root growth inhibition. Finally, I will discuss the significance of the rapid response pathways outside of the context of the root of Arabidopsis thaliana.