Human SOD1 is secreted via a conventional secretion pathway in Saccharomyces cerevisiae

Soluble proteins sorted through the secretory pathway contain an N-terminal signal peptide that induces their translocation into the endoplasmic reticulum (ER) from the cytosol. However, a few proteins that lack a signal peptide are still translocated into the ER, such as SOD1. SOD1 is a causative gene of amyotrophic lateral sclerosis (ALS). A relationship has been suggested between the secretion of SOD1 and the pathogenesis of ALS; however, the transport mechanism of SOD1 remains unclear. We herein report that SOD1 was translocated into the ER lumen through the translocon Sec61 and was then secreted extracellularly. The present results indicate the potential of suppressing the secretion of SOD1 as a therapeutic target for ALS.(c) 2023 Elsevier Inc. All rights reserved.

Automated summary

Soluble proteins with a signal peptide are translocated into the endoplasmic reticulum (ER), while some proteins without a signal peptide, like SOD1, can still enter the ER. SOD1 is a causative gene of ALS, and its secretion has been implicated in the pathogenesis of ALS. This study reveals that SOD1 is translocated into the ER lumen through the translocon Sec61 and subsequently secreted extracellularly, suggesting the potential of targeting SOD1 secretion as a therapeutic approach for ALS.