Table II
Selected cation/proton antiporters found in Arabidopsis
| Family | Gene Name | AGI Genome Codes | Residues | Topology | Substrate | Cellular Location |
|---|---|---|---|---|---|---|
| CaCA | CAX1 | At2g38170 | 459 | 9–11 TM | Ca2+/H+ | EM |
| CAX2 | At3g13320 | 439 | 7–11 TM | Cd2+, Ca2+, Mn2+/H+ | VM | |
| CAX3/HCX1 | At3g51860 | 448 | 8–10 TM | – | ? | |
| CAX7 | At5g17860 | 570 | 9–15 TM | – | ? | |
| MHX1 | At2g47600 | 539 | 10 TM | Mg2+, Zn2+/H+ | VM | |
| CPA1 | NHX1 | At5g27150 | 538 | 12 TM | Na+/H+ | VM |
| SOS1/NHX7 | At2g01980 | 1,162 | 12 TM | Na+/H+ | VM | |
| NHX8 | At1g14660 | 697 | 9 TM | – | PM? | |
| CPA2 | CHX6 | At1g08140 | 1,536 | 24 TM | – | – |
| CHX7 | At2g28170 | 617 | 12 TM | – | – | |
| CHX17 | At4g23700 | 820 | 10–13 TM | – | – | |
| CHX23 | At1g05580 | 1,193 | 12 TM | – | – | |
| KEA1 | At1g01790 | 618 | 10 TM | K+/H+ | – | |
| NhaD | NHD2 | At1g49810 | 420 | 6–10 TM | – | – |
EM, Endomembrane; VM, vacuolar membrane; PM, plasma membrane.