InterPro domain: IPR010291

The proteins in this family are represented by UNC-93 from Caenorhabditis elegans and also includes protein unc-93 homologue A (UNC93A), protein unc-93 homologue B1 (UNC93B1), and UNC93-like protein MFSD11 (also called major facilitator superfamily domain-containing protein 11 or protein ET). UNC-93 colocalizes with SUP-10 and SUP-9 within muscle cells. UNC-93 acts as a regulatory subunit of a multi-subunit potassium channel complex that may function in coordinating muscle contraction in C. elegans [ 1 ]. UNC93B1 controls intracellular trafficking and transport of a subset of Toll-like receptors (TLRs), including TLR3, TLR7 and TLR9, from the endoplasmic reticulum to endolysosomes where they can engage pathogen nucleotides and activate signaling cascades [ 2 ]. MFSD11 is ubiquitously expressed in the periphery and the central nervous system of mice, where it is expressed in excitatory and inhibitory mouse brain neurons [ 3 ].

1. sup-9, sup-10, and unc-93 may encode components of a two-pore K+ channel that coordinates muscle contraction in Caenorhabditis elegans. J. Neurosci. 23, 9133-45
2. Inhibiting TLR9 and other UNC93B1-dependent TLRs paradoxically increases accumulation of MYD88L265P plasmablasts in vivo. Blood 128, 1604-8
3. The Putative SLC Transporters Mfsd5 and Mfsd11 Are Abundantly Expressed in the Mouse Brain and Have a Potential Role in Energy Homeostasis. PLoS One 11, e0156912