The function of this family of transmembrane proteins is unknown. In vertebrates, proteins in this family are located in the lysosomal membrane and late endosome [1-2]. In Arabidopsis, a member of this family has been found to weakly interact with FRIGIDA, a determinant of flowering time [3].

1: Molecular characterisation of 'transmembrane protein 192' (TMEM192), a novel protein of the lysosomal membrane. Schroder B, Wrocklage C, Hasilik A, Saftig P; Biol Chem. 2010;391:695-704. PMID:20370317

2: Two dileucine motifs mediate late endosomal/lysosomal targeting of transmembrane protein 192 (TMEM192) and a C-terminal cysteine residue is responsible for disulfide bond formation in TMEM192 homodimers. Behnke J, Eskelinen EL, Saftig P, Schroder B; Biochem J. 2011;434:219-231. PMID:21143193

3: FRIGIDA delays flowering in Arabidopsis via a cotranscriptional mechanism involving direct interaction with the nuclear cap-binding complex. Geraldo N, Baurle I, Kidou S, Hu X, Dean C; Plant Physiol. 2009;150:1611-1618. PMID:19429606