ER structural remodeling requires TAK1/ATAT1-induced microtubule acetylation

Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2023.04.20.537623v1?rss=1 Authors: Ortiz, H. R., Flores, P. C., Ramonett, A., Ahmed, T., Ellis, N. A., Langlais, P. R., Karthikeyan, M., Lee, N. Y. Abstract: Dynamic changes in the endoplasmic reticulum (ER) morphology are central to maintaining cellular homeostasis. Microtubules (MT) facilitate the continuous remodeling of the ER network into sheets and tubules by coordinating with many ER-shaping protein complexes, although how this process is controlled by extracellular signals remains unknown. Here we report that TAK1, a kinase responsive to numerous growth factors and cytokines including TGF-beta and TNF-alpha, triggers ER tubulation by activating aTAT1, an MT-acetylating enzyme that enhances ER-sliding. We show that this TAK1/aTAT-dependent ER remodeling promotes cell survival by actively downregulating BOK, an ER membrane-associated proapoptotic effector. While BOK is normally protected from degradation when complexed with IP3R, it is rapidly degraded upon their dissociation during the ER sheets-to-tubules conversion. These findings demonstrate a distinct mechanism of ligand-induced ER remodeling and suggest that the TAK1/aTAT pathway may be a key target in ER stress and dysfunction. Copy rights belong to original authors. Visit the link for more info Podcast created by Paper Player, LLC