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 vol. 596 p. 1165 - 1177

0014-5793

The ubiquitin–proteasome system (UPS) degrades intracellular proteins through the 26S proteasome. We analysed how cold stress affects the UPS in glial cells. Together with a reduction in the 20S proteolytic activity and increased levels of polyubiquitinated proteins, exposure of glial cell cultures to cold induces a partial disassembly of the 26S proteasome. In particular, we found that Rpt5, a subunit of the 19S proteasome, relocates to cold-stable microtubules, although no apparent cytoskeletal redistribution was detected for 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 α-tubulin modulate the association of Rpt5 with microtubules. This reversible association could be related to functional preservation of the proteolytic complex during cold stress.