{Reference Type}: Case Reports
{Title}: S1P defects cause a new entity of cataract, alopecia, oral mucosal disorder, and psoriasis-like syndrome.
{Author}: Chen F;Ni C;Wang X;Cheng R;Pan C;Wang Y;Liang J;Zhang J;Cheng J;Chin YE;Zhou Y;Wang Z;Guo Y;Chen S;Htun S;Mathes EF;de Alba Campomanes AG;Slavotinek AM;Zhang S;Li M;Yao Z;
{Journal}: EMBO Mol Med
{Volume}: 14
{Issue}: 5
{Year}: 05 2022 9
{Factor}: 14.26
{DOI}: 10.15252/emmm.202114904
{Abstract}: In this report, we discovered a new entity named cataract, alopecia, oral mucosal disorder, and psoriasis-like (CAOP) syndrome in two unrelated and ethnically diverse patients. Furthermore, patient 1 failed to respond to regular treatment. We found that CAOP syndrome was caused by an autosomal recessive defect in the mitochondrial membrane-bound transcription factor peptidase/site-1 protease (MBTPS1, S1P). Mitochondrial abnormalities were observed in patient 1 with CAOP syndrome. Furthermore, we found that S1P is a novel mitochondrial protein that forms a trimeric complex with ETFA/ETFB. S1P enhances ETFA/ETFB flavination and maintains its stability. Patient S1P variants destabilize ETFA/ETFB, impair mitochondrial respiration, decrease fatty acid β-oxidation activity, and shift mitochondrial oxidative phosphorylation (OXPHOS) to glycolysis. Mitochondrial dysfunction and inflammatory lesions in patient 1 were significantly ameliorated by riboflavin supplementation, which restored the stability of ETFA/ETFB. Our study discovered that mutations in MBTPS1 resulted in a new entity of CAOP syndrome and elucidated the mechanism of the mutations in the new disease.