Solute carriers (SLCs) constitute the largest class of membrane transporters with more than 450 members. They show a high genetic, functional and structural variability and are increasingly acknowledged as an untapped source of potential new drug targets. One example is the sperm-specific SLC9C1 that belongs to the SLC9 superfamily of cation/proton antiporters, known as Na+/H+ exchangers (NHEs), which are essential for the regulation of intracellular pH, sodium homeostasis and cell volume. SLC9C1 was shown to be essential for male fertility and its expression shown to directly correlate with sperm count and motility. SLC9C1 sets itself apart from other SLCs by its unique domain composition, which is not found in any other membrane protein described to date. The transport domain (TD) is accompanied by a voltage-sensing domain (VSD) and a cyclic-nucleotide binding domain (CNBD), which are regulatory units usually found in voltage-gated cyclic-nucleotide-modulated ion channels, also referred to as CNBD ion channels. Here you can see recent cryoEM structure of the human ligand-free SpSLC9C1 solute carrier embedded within a lipid membrane model (PDB code: 8PCZ)

#molecularart ... #lipid ... #sperm ... #channel ... #carrier ... #solute ... #SpSLC9C1 .. #cryoem

Structure rendered with @proteinimaging and depicted with @corelphotopaint