>TIGR00840 b_cpa1 sodium/hydrogen exchanger 3; InterPro: IPR004709 Na^+/H^+ exchange proteins eject protons from cells, effectively eliminating excess acid from actively metabolising cells. Na^+/H^+ exchange activity is also crucial for the regulation of cell volume, and for the reabsorption of NaCl across renal, intestinal, and other epithelia. These antiports exchange Na^+ for H^+ in an electroneutral manner, and this activity is carried out by a family of Na^+/H^+ exchangers, or NHEs, which are known to be present in both prokaryotic and eukaryotic cells. In mammalian cells, Na^+/H^+ exchange activity is found in both the plasma membrane and inner mitochondrial membrane. To date, six mammalian isoforms have been identified (designated NHE1-NHE6) , . These exchangers are highly-regulated (glyco)phosphoproteins, which, based on their primary structure, appear to contain 10-12 membrane-spanning regions (M) at the N-terminus and a large cytoplasmic region at the C-terminus. The transmembrane regions M3-M12 share identity with other members of the family. The M6 and M7 regions are highly conserved. Thus, this is thought to be the region that is involved in the transport of sodium and hydrogen ions. The cytoplasmic region has little similarity throughout the family. There is some evidence that the exchangers may exist in the cell membrane as homodimers, but little is currently known about the mechanism of their antiport . ; GO: 0015385 sodium:hydrogen antiporter activity, 0006814 sodium ion transport, 0006885 regulation of pH, 0016021 integral to membrane.

Probab=99.28 E-value=1.8e-09 Score=82.15 Aligned_cols=357 Identities=15% Similarity=0.159 Sum_probs=202.1 Q ss_pred HHHHHHHHHHC--CCCHHHHHHHHHHHHCCHHCCCC----CCHHHHHH--HHHHHHHHHHHHHHHCCCHHHHHHHCCHHH Q ss_conf 99999999870--88867999999996274103855----84789999--999999999988254168899984151588 Q gi|254780924|r 11 AFIFGAIANRC--RLPTLIGYLVAGILVGPRTPGFV----ASQSLVPA--LAEIGIILLMFGVGLHFSVKDLISVRGIAL 82 (609) Q Consensus 11 a~i~g~la~rl--~lP~i~~~il~GillGp~~l~~i----~~~~~l~~--l~~lgl~~llF~~Gleld~~~l~~~~~~~~ 82 (609) T Consensus 21 ~Ki~fHl~~k~~~~vPES~LLi~~G~l~G~ii~~~~~hYi~~p~~l~s~~FF~~LLPPIvLdaGY~m~~r~Ff~Nlg~IL 100 (627) T TIGR00840 21 AKIGFHLTHKVLRVVPESVLLIVYGLLVGGIIKALDHHYIIDPPTLDSSLFFLYLLPPIVLDAGYFMPKREFFENLGSIL 100 (627) T ss_pred HHHHHHHCCCHHHHCHHHHHHHHHHHHHHHHHHHCCCCEEECCCCCCCCHHHHHCCHHHHHHHCCCCCCCHHHHHHHHHH T ss_conf 74442030101001306899999999999999734885661587206221353404056753011147740356689999 Q ss_pred HHHHHHHHHHHHHHHHHHHH----H-----CCCHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCCCHHHHHHHHHHHHHH Q ss_conf 99899999999999999999----6-----78868999999999742389999876565541144057898998777789 Q gi|254780924|r 83 PGALIQIILGTALGALMGMV----M-----GWSLGGSVVFGLALSIASTVVLLKALQENRILETDRGKIAVGWLIVEDLI 153 (609) Q Consensus 83 ~~~~~~~~~~~~~~~~~~~~----l-----g~~~~~all~g~~l~~ts~~vv~~~l~~~~~~~~~~g~~~~~~~~~~Di~ 153 (609) T Consensus 101 ~fAv~GT~~~A~~~G~~lY~i~~~~~~~~~~IglLd~llfGsliSAVDPVaVLavFeE~~V~~~L~-iliFGESLLNDAv 179 (627) T TIGR00840 101 LFAVVGTLINAFVLGLSLYGICLIGGFGSIDIGLLDNLLFGSLISAVDPVAVLAVFEELHVNEKLY-ILIFGESLLNDAV 179 (627) T ss_pred HHHHHHHHHHHHHHHHHHHHHHHHHCCCCCCHHHHHHHHHHHHHHHHCCHHHHHHHHHHHCCCCEE-EEEECHHHHCCHH T ss_conf 999999999999999999999997502301055899999999986315147887887552187114-7875233330425 Q ss_pred HHHHHHHHHHHHCC--CCCCCHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCCCEEEEEECCCCCHHHHHHHCCCCC Q ss_conf 99999999986134--4433013567899998876532101479999999841010000100034454387764203567 Q gi|254780924|r 154 IVLALVLIPAAATN--YSAEPSSMTHPWTSFITQQMGFEVGMPGLIMITLLKVVAFIGVMLIFGRRVIPWILHMIFYTGS 231 (609) Q Consensus 154 ~i~~l~il~~~~~~--~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 231 (609) T Consensus 180 tvVLY~~~~~f~~~sD~~~e~~t~vdv~~G~~~-fF~v~~G~G~L~Gv~~----------G~----~~af~~rft~~~rY 244 (627) T TIGR00840 180 TVVLYNTFEKFIKLSDASDEAVTIVDVVEGCVS-FFVVTLGVGLLVGVVF----------GF----LVAFITRFTKHIRY 244 (627) T ss_pred HHHHHHHHHHHHHCCCCCCCCEEEEHHHHHHHH-HHHHHHHHHHHHHHHH----------HH----HHHHHHHHCCCCCC T ss_conf 678999999984004688652133203324544-6666454889999999----------99----99999751045204 Q ss_pred HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCCCC---HHHHHHHHHHHH----HHHHHHHHHHHHHHHC-CH Q ss_conf 368999999999999998887411002466666422202761---456899999766----8999999998865311-47 Q gi|254780924|r 232 RELFRLGVLAIALGFAYGSSKLFGVSLSLGAFFAGMILAESE---LSQSAAQESLPL----RDAFSVLFFISVGMMF-NP 303 (609) Q Consensus 232 ~~~~~~~~l~~~~~~~~~~~~~~g~s~~lgaf~aG~~l~~~~---~~~~~~~~~~~~----~~~~~~~fFv~iG~~l-~~ 303 (609) T Consensus 245 P~IE-P~fvl~~sYlsYL~aE~~hlSGIlA~~~Cg~~m~~Yv~~N~S~~S~~TikY~~K~lsS~SEt~IFifLGvs~V~~ 323 (627) T TIGR00840 245 PVIE-PLFVLLISYLSYLLAETLHLSGILALIFCGITMKKYVEANISRESETTIKYFMKMLSSLSETLIFIFLGVSLVSE 323 (627) T ss_pred CCCC-HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHCCC T ss_conf 6520-489999999999998778899999999989999888875213313789999999887788999999872420056 Q ss_pred HHHHHHH--HHHHHHHHHHH---------------HHHHHHHHHHHCCCC--------CCHHHHHHHHHHHCCCCHHHHH Q ss_conf 9886202--56777765554---------------221223211000255--------8799999986432122025678 Q gi|254780924|r 304 DILISNP--ILLMMAVIIVI---------------IGKALIAFIVVIAFG--------RSVATALTIAASLSQIGEFSFI 358 (609) Q Consensus 304 ~~l~~~~--~~~l~~~~~~~---------------~~k~~~~~~~~~~~~--------~~~~~~~~~g~~l~~~g~~~~v 358 (609) T Consensus 324 ~~~w-~w~~~fv~~Tl~~C~aRWCavfPLsqfvnWiyR~~~v~~l~~~~N~f~S~~~~~~~~DQ~~~~yaGl-RGAv~f~ 401 (627) T TIGR00840 324 NHEW-NWPLAFVVVTLVFCVARWCAVFPLSQFVNWIYRVLGVLTLSWILNEFRSVKVELPFKDQLVIFYAGL-RGAVAFA 401 (627) T ss_pred CEEE-EHHHHHHHHHHHHHHHHHHHHCCHHHHHHHHHHHHHHHHHHHHHCCCCEECCCCCCCCEEEEEECHH-HHHHHHH T ss_conf 1267-3028999999999863354522268899999999999999887515320102115312177862126-7899999 Q ss_pred HHHHHHHCCCCCHHHH--HHHHHHHHHHHHH Q ss_conf 8988764178786687--7877888999999 Q gi|254780924|r 359 LANLGVELGILPDQAR--DLILASSIISIIL 387 (609) Q Consensus 359 ~a~~a~~~g~i~~~~~--~~i~~~~~~s~~i 387 (609) T Consensus 402 L-~~lld~~~~~~K~lfvtt~L~V~f~TVi~ 431 (627) T TIGR00840 402 L-ALLLDEKIFPAKKLFVTTTLVVVFFTVIF 431 (627) T ss_pred H-HHHCCCCCCCCCHHHHEEEEEEEEEEEEE T ss_conf 9-88504443531003310000167766324

HHsearch alignment for GI: 254780924 and conserved domain: TIGR00840