Honeybee Brain Oscillations Are Generated by Microtubules. The Concept of a Brain Central Oscillator

Microtubules (MTs) are important structures of the cytoskeleton in neurons. Mammalian brain MTs act as biomolecular transistors that generate highly synchronous electrical oscillations. However, their role in brain function is largely unknown. To gain insight into the MT electrical oscillatory activity of the brain, we turned to the honeybee (Apis mellifera) as a useful model to isolate brains and MTs. The patch clamp technique was applied to MT sheets of purified honeybee brain MTs. High resistance seal patches showed electrical oscillations that linearly depended on the holding potential between ± 200 mV and had an average conductance in the order of ~9 nS. To place these oscillations in the context of the brain, we also explored local field potential (LFP) recordings from the Triton X-permeabilized whole honeybee brain unmasking spontaneous oscillations after but not before tissue permeabilization. Frequency domain spectral analysis of time records indicated at least two major peaks at approximately ~38 Hz and ~93 Hz in both preparations. The present data provide evidence that MT electrical oscillations are a novel signaling mechanism implicated in brain wave activity observed in the insect brain.Fil: Gutierrez, Brenda Celeste. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo. - Universidad Nacional de Santiago del Estero. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo.; ArgentinaFil: Pita Almenar, Marcelo R.. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo. - Universidad Nacional de Santiago del Estero. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo.; ArgentinaFil: Martínez, Luciano J.. Centro Integral de Microscopía Electrónica; ArgentinaFil: Siñeriz Louis, Manuel. Centro Integral de Microscopía Electrónica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Albarracín, Virginia Helena. Centro Integral de Microscopía Electrónica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cantero, Maria del Rocio. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo. - Universidad Nacional de Santiago del Estero. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo.; ArgentinaFil: Cantiello, Horacio Fabio. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet Noa Sur. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo. - Universidad Nacional de Santiago del Estero. Instituto Multidisciplinario de Salud, Tecnologia y Desarrollo.; Argentin