Small integral membrane protein 27 (SMIM27)

Small integral membrane protein 27 (SMIM27) is a protein-coding gene product predicted to be a single-pass integral membrane protein primarily localized to cellular membranes. The gene is also known as C9orf133 or TOPORS antisense RNA 1 (TOPORS-AS1), reflecting its genomic location near the TOPORS gene on chromosome 9[3][5]. The biological function of SMIM27 is not well understood, and gene ontology resources predict membrane association with unknown specific molecular activity. Although it has been linked to ovarian cancer through bioinformatics or genomic studies, its causal or functional role in disease remains undefined[3]. Importantly, neither receptors, enzymatic activity, nor transporter function have been established for SMIM27, and it is not recognized as a therapeutic target in major drug or protein databases as of 2025[3][1][6]. The alternative names "TOPORS-AS1" and "TOPORS antisense RNA 1" indicate the historical annotation of the locus as a non-coding RNA gene; however, recent database entries classify SMIM27 as a protein-coding gene, reflecting updated genome annotations[3][5]. There are no reliable data supporting roles in established signaling pathways, nor experimental data describing ligand, drug, or protein-protein interactors[1][3][6]. Some confusion may arise from the locus being called both a protein-coding gene and a non-coding RNA gene depending on the database and annotation version; current consensus designates it as a protein-coding locus[3]. No evidence links SMIM27 with specific physiological or pathological mechanisms beyond rudimentary disease associations produced by computational analyses. Small integral membrane protein 27 (SMIM27) is a predicted single-pass integral membrane protein of unknown biological function, not currently recognized as a validated drug target, with limited information regarding molecular function, interaction partners, or involvement in human disease[3][5][1].

Other names

C9orf133TOPORS-AS1TOPORS antisense RNA 1small integral membrane protein 27