Electrical oscillations generated by different structures of brain microtubules

CANTERO MR; PEREZ PL; SCARINCI N; GUTIERREZ BC; BONACINA J; CANTIELLO HF

Workshop; EMBO Workshop Emerging Concepts of the Neuronal Cytoskeleton 5th Edition.; 2019

Cantero MR, Perez PL, Scarinci N, Gutierrez BC, Bonacina J, Cantiello HF

Electrical oscillations generated by different structures of brain microtubulesMicrotubules (MTs) are long cylindrical cytoskeletal structures that control cell division,intracellulartransport,andtheshapeofcells.MTsalsoformdifferentstructures,suchassheetsand bundles that are particularly prominent in neurons where they help define axons anddendrites.AlthoughMTshavealargeelectricaldipoleandareeasilyorientedinelectricfields,their electrical properties have only recently been unmasked. MTs are bio-electrochemicaltransistorsthatformnonlinearelectricaltransmissionlines.HerewepresentevidencethatMTstructures from different origins including, murine, bovine, and apian brains, spontaneouslygenerateelectricaloscillationsandburstsofelectricalactivitysimilartoactionpotentials.Underintracellular-like conditions, voltage-clamped MT sheets and bundles displayed highly stableelectricaloscillationsthatrepresented,inaverage,a258%- 640%changeinionicconductance.Theseoscillationshadfundamentalfrequenciesintherangeof29Hzto39Hz,andprogressedthrough various periodic regimes. Interestingly, voltage-clamped membrane-permeabilizedneuritesofculturedmousehippocampalneuronswerealsocapableofboth,thegenerationofelectricaloscillationsandtheaxialconductionoftheelectricalsignals.Ourfindingsareconsistentwithafunctionalmodelthatincludesbothagatingmechanismandtheconductivepathwayofthe oscillator. The encompassed data indicate that the electrical oscillations are an intrinsicproperty ofMTs, which may have relevant implications in the control of neuronal functions,including the gating and regulation of excitable ion channels, which, in turn, may aid in theunderstandingofhigher brainfunctionssuchasmemoryandconsciousness.