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dc.contributor.advisorBates, Emily A.
dc.contributor.authorBuscaglia, Georgia Christine
dc.contributor.committeememberPerson, Abigail
dc.contributor.committeememberMoore, Jeffrey
dc.contributor.committeememberFranco, Santos
dc.contributor.committeememberKennedy, Matthew
dc.contributor.committeememberMacklin, Wendy
dc.contributor.committeememberNiswander, Lee
dc.date.accessioned2020-06-29T10:03:05Z
dc.date.available2020-06-29T10:03:05Z
dc.date.submitted2020
dc.descriptionIncludes bibliographical references.
dc.descriptionSpring
dc.description.abstractDeveloping neurons undergo dramatic morphological changes to appropriately migrate and extend axons to make synaptic connections. The microtubule cytoskeleton, made of alpha/beta-tubulin dimers, drives neurite outgrowth, promotes neuronal growth cone responses, and facilitates intracellular transport of critical cargoes during neurodevelopment and in adulthood. The mechanisms by which neurons regulate microtubule network assembly and organization to respond appropriately to external cues are largely unknown. Cells express different alpha and beta tubulin genes, or isotypes, providing one potential level of microtubule regulation. TUBA1A is the most abundant alpha-tubulin isotype in the developing brain and mutations to TUBA1A in humans cause severe brain malformations. The role of TUBA1A in the adult brain is largely unknown. We use a loss-of-function mutation to Tuba1a, Tuba1aN102D, to investigate requirements for Tuba1a in developing and adult neurons. Tuba1aND substitution reduced the amount of Tuba1a protein and prevented incorporation of Tuba1a into cellular microtubule polymers. Tuba1aND/+ neurons with reduced Tuba1a had altered microtubule dynamics and slower neuron outgrowth compared to controls. Reduced Tuba1a alpha-tubulin impacted axon extension and impaired formation of forebrain commissures in vivo, supporting a role for Tuba1a in axon guidance. Neurons deficient in Tuba1a failed to localize microtubule associated protein-1b (Map1b) to the developing growth cone, likely impacting reception of developmental guidance cues. Further, we show that neurons with reduced Tuba1a had diminished axonal microtubule density and impaired intracellular transport. We demonstrate that Tuba1a is a major component of adult brain alpha-tubulin, implicating Tuba1a in adult neuronal microtubule function. Tuba1aND/+ heterozygous mice had approximately half the amount of brain alpha-tubulin as wild-type at birth, but normal alpha-tubulin abundance in adult Tuba1aND/+ brains. Despite this, Tuba1aND/+ neuromuscular junction synapses deteriorated with age, leading to adult-onset behavioral deficits. Overall, we show that reduced Tuba1a is sufficient to support neuronal migration, but not axon guidance. We further show that the Tuba1a-rich microtubule tracks assembled during development are essential for mature neuron function and maintenance of synapses over time. These data provide mechanistic insight as to how TUBA1A tunes microtubule function to support neurodevelopment, and investigate novel functions of TUBA1A in the adult nervous system.
dc.format.mediumborn digital
dc.format.mediumdoctoral dissertations
dc.identifierBuscaglia_ucdenveramc_1639D_10724.pdf
dc.identifier.urihttps://hdl.handle.net/10968/5495
dc.languageEnglish
dc.publisherUniversity of Colorado at Denver, Anschutz Medical Campus. Health Sciences Library
dc.relation.ispartof2017 to Current
dc.rightsCopyright of the original work is retained by the author.
dc.subjectneurodevelopment
dc.subjectTUBA1A
dc.subjecttrafficking
dc.subject.meshCytoskeleton
dc.subject.meshMicrotubules
dc.subject.meshTubulin
dc.titleTuba1a microtubules establish the foundations for neuronal function
dc.typeText
thesis.degree.disciplineNeuroscience
thesis.degree.grantorUniversity of Colorado at Denver, Anschutz Medical Campus
thesis.degree.levelDoctoral
thesis.degree.nameDoctor of Philosophy (Ph.D.)


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