2.A.20.2.3
Gibbon ape leukemia virus receptor 2/sodium-dependent phosphate uptake transporter, P_i:Na⁺ symporter, PiT2, PiT-2, GLVR2, SLC20A2. Mapping of the minimal transporting unit suggested a structure universal to all PiT-related proteins (Battger and Pedersen, 2011).The protein can transport P_i in the absence of Na⁺, and mutations allow Na⁺ transport in the absence of P_i. Transmembrane amino acids E(55) and E(575) appear to be responsible for linking P_i import to Na⁺symport (Bøttger et al. 2006). SLC20A2 variants cause the loss of Pi transport activity in mammalian cells (Sekine et al. 2019). Mutation of SLC20A2 seems to cause hereditary multiple exostoses (Li et al. 2020). It has been associated with Primary Familial Brain Calcification (PFBC) (Wang et al. 2012; Monfrini et al. 2023). Inorganic phosphate exporter heterozygosity in mice leads to brain vascular calcification, microangiopathy, and microgliosis (Maheshwari et al. 2023).