Actin Filaments Modulate Electrical Activity of Brain Microtubules

BRENDA C. GUTIERREZ; MARÍA DEL ROCÍO CANTERO; CANTIELLO, HORACIO F.

ROSARIO

Simposio; REUNIÓN ANUAL SAFIS; 2019

SOCIEDAD ARGENTINA DE FISIOLOGÍA

Abstract. The cytoskeleton of eukaryotic cells contains networks of actin filaments and microtubules (MTs) that are jointly implicated in various cell functions, including cell division, morphogenesis and migration. In neurons, this synergistic activity drives both the formation of axons during neuronal development and synaptic activity in mature neurons. Both actin filaments and MTs are highly charged polyelectrolytes that generate and conduct electrical signals. However, information on an electrical crosstalk between these two cytoskeletal networks is unavailable. Herein we tested the effect of actin polymerization on the electrical oscillations generated by two-dimensional sheets of MTs. Voltage-clamped bovine brain MT sheets displayed spontaneous electrical oscillations that represented a synchronous 224% change in MT conductance, with a fundamental frequency of 38 Hz. The integrated charge transferred per second was 4.15 nC at 60 mV that increased 72.3% (7.15 nC) after addition of monomeric (G)-actin. This phenomenon had a 2-min lag time and was prevented by G actin-binding protein DNAse I. Addition of pre-polymerized F-actin, however had a rapid onset (