The 19S proteasome subunit Rpt5 reversibly associates with cold stable microtubules in glial cells at low temperatures

FLORES MARTIN, JÉSICA BELÉN; BONNET, LAURA VANESA; PALANDRI, ANABELA; ZAMANILLO HERMIDA, SOFÍA; HALLAK, MARTA ELENA; GALIANO, MAURICIO RAUL

FEBS LETTERS

ELSEVIER SCIENCE BV

Año: 2022

0014-5793

The ubiquitin proteasome system (UPS) degrades intracellular proteinsthrough the 26S proteasome. We analysed how cold stress affects the UPS inglial cells. Together with a reduction in the 20S proteolytic activity andincreased levels of polyubiquitinated proteins, exposure of glial cell culturesto cold induces a partial disassembly of the 26S proteasome. In particular,we found that Rpt5, a subunit of the 19S proteasome, relocates to cold-stablemicrotubules, although no apparent cytoskeletal redistribution was detectedfor other analysed subunits of the 19S or 20S complexes. Furthermore, we demonstrate that both the expression of the microtubule-associated protein MAP6 and the post-translational acetylation of a-tubulin modulate the associationof Rpt5 with microtubules. This reversible association could be relatedto functional preservation of the proteolytic complex during cold stress.