Development and maintenance of synaptic structure is mediated by the alpha-tubulin acetyltransferase MEC-17/αTAT1

2019 ◽  
Author(s):  
Jean-Sébastien Teoh ◽  
Wenyue Wang ◽  
Gursimran Chandhok ◽  
Roger Pocock ◽  
Brent Neumann

Microtubules are fundamental elements of neuronal structure and function. They are dynamic structures formed from protofilament chains of α- and β-tubulin heterodimers. Acetylation of the lysine 40 (K40) residue of α-tubulin protects microtubules from mechanical stresses by imparting structural elasticity. The enzyme responsible for this acetylation event is MEC-17/αTAT1. However, despite its functional importance, the consequences of MEC-17/αTAT1 misregulation on neuronal structure and function are incompletely defined. Using overexpression and loss of function approaches, we have analysed the effects of MEC-17 misregulation on the development and maintenance of synaptic branches in the mechanosensory neurons of Caenorhabditis elegans. We find that synaptic branch extension is delayed, and that synaptogenesis is defective in these animals. Strikingly, by adulthood the synaptic branches specifically and spontaneously degenerate. This phenotype is dependent on the acetyltransferase domain on MEC-17, revealing that correct levels of K40 acetylation are essential for the maintenance of neuronal structure. Finally, we investigate the genetic pathways in which mec-17 functions, uncovering novel interactions with dual leucine-zipper kinase dlk-1 and the focal adhesion gene zyx-1/Zyxin. These interactions link MEC-17 together with factors involved in neuronal and actin remodelling to protect synaptic branches. Together, our results reveal that appropriate levels of α-tubulin K40 acetylation by MEC-17 are crucial for the development and maintenance of neuronal architecture.

Neuron ◽  
2021 ◽  
Author(s):  
Amanda M. Vanderplow ◽  
Andrew L. Eagle ◽  
Bailey A. Kermath ◽  
Kathryn J. Bjornson ◽  
Alfred J. Robison ◽  
...  

2010 ◽  
Vol 43 (4) ◽  
pp. 341-352 ◽  
Author(s):  
Charu Misra ◽  
Sophie Restituito ◽  
Jainne Ferreira ◽  
Gerald A. Rameau ◽  
Jie Fu ◽  
...  

1998 ◽  
Vol 111 (3) ◽  
pp. 313-320 ◽  
Author(s):  
K.A. Johnson

Little is known of the molecular basis for the diversity of microtubule structure and function found within the eukaryotic flagellum. Antibodies that discriminate between tyrosinated alpha tubulin and post-translationally detyrosinated alpha tubulin were used to localize these complementary tubulin isoforms in flagella of the single-celled green alga Chlamydomonas reinhardtii. Immunofluorescence analysis of intact axonemes detected both isoforms along most of the lengths of flagella; however, each had a short distal zone rich in tyrosinated tubulin. Localizations on splayed axonemes revealed that the microtubules of the central-pair apparatus were rich in tyrosinated tubulin, while outer doublets contained a mixture of both isoforms. Immunoelectron analysis of individual outer doublets revealed that while tyrosinated tubulin was present in both A and B tubules, detyrosinated tubulin was largely confined to the wall of the B hemi-tubules. The absence of detyrosinated tubulin from the A tubules of the outer doublets and the microtubules of the central pair, both of which extend past the B hemi-tubules of the outer doublets in the flagellar tip, explained the appearance of a tyrosinated tubulin-rich distal zone on intact axonemes. Localizations performed on cells regenerating flagella revealed that flagellar assembly used tyrosinated tubulin; detyrosination of the B tubule occurred during later stages of regeneration, well after microtubule polymerization. The developmental timing of detyrosination, which occurs over a period during which the regrowing flagella begin to beat more effectively, suggests that post-translational modification of the B tubule surface may enhance dynein/B tubule interactions that power flagellar beating.


2018 ◽  
Vol 84 (7) ◽  
pp. 478-487 ◽  
Author(s):  
Kaichuan Zhu ◽  
Finn Peters ◽  
Severin Filser ◽  
Jochen Herms

2010 ◽  
Vol 38 (2) ◽  
pp. 443-444 ◽  
Author(s):  
Nils Brose ◽  
Vincent O'Connor ◽  
Paul Skehel

Synaptopathy is an increasingly popular term used to define key features of neurodegenerative and psychiatric disease. It implies that disruptions in synaptic structure and function are potentially the major determinant of such brain diseases. The Synaptopathies: Dysfunction of Synaptic Function Biochemical Society Focused Meeting brought together several invited speakers, supplemented with short communications from young scientists, who addressed this possibility. The talks spanned the full gamut of approaches that brought molecular, cellular, systems and whole-animal experimentation together to address how fundamental synaptic biology was increasingly informing on dysfunction in disease. The disease and models thereof discussed included Alzheimer's disease, prions, Huntington's disease, Parkinson's disease, schizophrenia and autism. The audience were asked to reflect on whether synaptopathy, although attractive and conceptually useful, provided a significant explanation as the cause of these major diseases. The breadth of the meeting reinforced the complexity of these brain diseases, supported the significance of synaptic dysfunction in disease, but left open the issue as to whether the prime cause of these disorders could be resolved as simple synaptic dysfunction. Thus, despite revealing a value of synaptopathy, further investigation will be required to reveal its balance in the cause and effect in each of the major brain diseases.


Sign in / Sign up

Export Citation Format

Share Document