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bioRxiv · 10.1101/2022.07.02.498566

Chemical Proteomics Reveals Protein Tyrosination Extends Beyond the Alpha-Tubulins in Human Cells.

Makarov, D.·Kielkowski, P.
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Abstract

Tubulin detyrosination-tyrosination cycle regulates the stability of microtubules. Thus far described on -tubulins, the tyrosination level is maintained by a single tubulin-tyrosine ligase (TTL). However, the precise dynamics and tubulin isoforms which undergo (de)tyrosination in neurons are unknown. Here, we exploit the substrate promiscuity of the TTL to introduce an O-propargyl-L-tyrosine in neuroblastoma cells and neurons. Mass spectrometry-based chemical proteomics in neuroblastoma cells using the O-propargyl-L-tyrosine probe revealed previously discussed tyrosination of TUBA4A, MAPRE1, and other non-tubulin proteins. This finding was further corroborated in differentiating neurons. Together we present the method for tubulin tyrosination profiling in living cells. Our results show that detyrosination-tyrosination is not restricted to -tubulins with coded C-terminal tyrosine and is thus involved in fine-tuning of the tubulin and non-tubulin proteins during neuronal differentiation.

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Makarov, D., Kielkowski, P.. 2022-07-03. Chemical Proteomics Reveals Protein Tyrosination Extends Beyond the Alpha-Tubulins in Human Cells.. https://doi.org/10.1101/2022.07.02.498566

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