The COP9 signalosome mediates the Spt23 regulated fatty acid desaturation and ergosterol biosynthesis
The COP9 signalosome (CSN) is a conserved eukaryotic complex, essential for vitality in all multicellular organisms and critical for the turnover of key cellular proteins through catalytic and non-catalytic activities. Saccharomyces cerevisiae is a powerful model organism for studying fundamental aspects of the CSN complex. This CSN includes a conserved enzymatic core but lacks few subunits that participate in non-catalytic activities, probably explaining its non-essentiality for life. A previous transcriptomic analysis of an S.