TUBA1A, encoding tubulin alpha 1a, is a crucial gene involved in microtubule assembly. Microtubules, made of α/β-tubulin dimers, are essential for neurite outgrowth, neuronal growth cone responses, and intracellular transport during neurodevelopment [2]. TUBA1A constitutes a major part of α-tubulin in the developing brain [2].

In Tuba1aND/+ mice (a loss-of-function model), α-tubulin levels are reduced in juvenile brains. In postnatal day 0 cultured neurons from these mice, reduced TUBA1A leads to less microtubule assembly in axons, causing more pausing during organelle trafficking. These mice develop adult-onset ataxia, indicating that TUBA1A-rich microtubule tracks are essential for mature neuron function and synapse maintenance [1]. In another study, the Tuba1aND/+ mice showed normal brain formation except for significant impacts on axon extension and impaired formation of forebrain commissures. Neurons with reduced Tuba1a due to the Tuba1aND mutation had slower outgrowth and failed to localize microtubule-associated protein-1b to the growth cone, likely affecting microtubule stabilization [2].

In conclusion, TUBA1A is vital for microtubule-related functions in neuronal development and maintenance. The Tuba1a loss-of-function mouse models have revealed its role in processes such as axon extension, commissure formation, organelle trafficking, and the maintenance of mature neurons and synapses. Mutations in TUBA1A are associated with severe brain malformations and neurological defects, highlighting its importance in understanding related disease mechanisms [1,2].

References:

1. Buscaglia, Georgia, Northington, Kyle R, Moore, Jeffrey K, Bates, Emily Anne. 2020. Reduced TUBA1A Tubulin Causes Defects in Trafficking and Impaired Adult Motor Behavior. In eNeuro, 7, . doi:10.1523/ENEURO.0045-20.2020. https://pubmed.ncbi.nlm.nih.gov/32184299/

2. Buscaglia, Georgia, Northington, Kyle R, Aiken, Jayne, Hoff, Katelyn J, Bates, Emily A. 2022. Bridging the Gap: The Importance of TUBA1A α-Tubulin in Forming Midline Commissures. In Frontiers in cell and developmental biology, 9, 789438. doi:10.3389/fcell.2021.789438. https://pubmed.ncbi.nlm.nih.gov/35127710/