Figure 2.

Schematic drawing illustrating conformational structures of TRPM5, PKD1L3, and PKD2L1. TRPM5 is predicted to have 6 transmembrane domains and to assemble as tetramers, containing 4 MHRs in the intracellular N-terminal region, and a TRP-motif and a putative coiled-coil domain in the intracellular C-terminal region. Mouse PKD1L3 is predicted to have 11 transmembrane domains, and contains an N-terminal CLD, 29 S/P-rich repeats, a GPS, and a PLAT/LH2 domain. Note that human PKD1L3 does not contain S/P-rich repeats, even in its genomic sequences. PKD2L1 is predicted to have 6 transmembrane domains and contains a putative Ca²⁺ binding EF hand motif and predicted coiled-coil domain in its C-terminal cytoplasmic tail. MHR, TRPM homology region; CLD, C-type lectin domain; S/P-rich repeats, serine/proline-rich repeats; GPS, G-protein-coupled receptor proteolytic site; PLAT, polycystin-1-lipoxygenase-alpha toxin; LH2, lipoxygenase homology 2; ER, endoplasmic recticulum retention signal; EF hand, calcium-binding domain. Portions of this Figure were modified from Fig.1 in Delmas et al. (2004).