Sodium-hydrogen exchange regulatory cofactor NHE-RF2 (NHERF-2) also known as tyrosine kinase activator protein 1 (TKA-1) or SRY-interacting protein 1 (SIP-1) is a protein that in humans is encoded by the SLC9A3R2 (solute carrier family 9 isoform A3 regulatory factor 2) gene.[1][2]
NHERF-2) is a scaffold protein that connects plasma membrane proteins with members of the ezrin/moesin/radixin family and thereby helps to link them to the actincytoskeleton and to regulate their surface expression. It is necessary for cAMP-mediated phosphorylation and inhibition of SLC9A3. In addition, it may also act as scaffold protein in the nucleus.
This regulatory protein (factor) interacts with a sodium/hydrogen exchanger NHE3 (SLC9A3) in the brush border membrane of the proximal tubule, small intestine, and colon that plays a major role in transepithelial sodium absorption. SLC9A3R2, as well as SLC9A3R1 and protein kinase A phosphorylation, may play a role in NHE3 regulation.[3]
↑Poulat F, de Santa Barbara P, Desclozeaux M, Soullier S, Moniot B, Bonneaud N, Boizet B, Berta P (March 1997). "The human testis determining factor SRY binds a nuclear factor containing PDZ protein interaction domains". J. Biol. Chem. 272 (11): 7167–72. doi:10.1074/jbc.272.11.7167. PMID9054412.
↑ 4.04.1Chun, Jaesun; Kwon Taegun; Lee Eunjung; Suh Pann-Ghill; Choi Eui-Ju; Sun Kang Sang (October 2002). "The Na(+)/H(+) exchanger regulatory factor 2 mediates phosphorylation of serum- and glucocorticoid-induced protein kinase 1 by 3-phosphoinositide-dependent protein kinase 1". Biochem. Biophys. Res. Commun. United States. 298 (2): 207–15. doi:10.1016/S0006-291X(02)02428-2. ISSN0006-291X. PMID12387817.
↑Yun, C Chris; Chen Yueping; Lang Florian (March 2002). "Glucocorticoid activation of Na(+)/H(+) exchanger isoform 3 revisited. The roles of SGK1 and NHERF2". J. Biol. Chem. United States. 277 (10): 7676–83. doi:10.1074/jbc.M107768200. ISSN0021-9258. PMID11751930.
↑Kim JH, Lee-Kwon W, Park JB, Ryu SH, Yun CH, Donowitz M (June 2002). "Ca(2+)-dependent inhibition of Na+/H+ exchanger 3 (NHE3) requires an NHE3-E3KARP-alpha-actinin-4 complex for oligomerization and endocytosis". J. Biol. Chem. United States. 277 (26): 23714–24. doi:10.1074/jbc.M200835200. ISSN0021-9258. PMID11948184.
↑Yun, C H; Lamprecht G; Forster D V; Sidor A (October 1998). "NHE3 kinase A regulatory protein E3KARP binds the epithelial brush border Na+/H+ exchanger NHE3 and the cytoskeletal protein ezrin". J. Biol. Chem. UNITED STATES. 273 (40): 25856–63. doi:10.1074/jbc.273.40.25856. ISSN0021-9258. PMID9748260.
↑Sitaraman, Shanthi V; Wang Lixin; Wong Michelle; Bruewer Matthias; Hobert Michael; Yun C-H; Merlin Didier; Madara James L (September 2002). "The adenosine 2b receptor is recruited to the plasma membrane and associates with E3KARP and Ezrin upon agonist stimulation". J. Biol. Chem. United States. 277 (36): 33188–95. doi:10.1074/jbc.M202522200. ISSN0021-9258. PMID12080047.
↑Li, Yong; Li Jian; Straight Samuel W; Kershaw David B (June 2002). "PDZ domain-mediated interaction of rabbit podocalyxin and Na(+)/H(+) exchange regulatory factor-2". Am. J. Physiol. Renal Physiol. United States. 282 (6): F1129–39. doi:10.1152/ajprenal.00131.2001. ISSN0363-6127. PMID11997330.
↑Sun, F; Hug M J; Lewarchik C M; Yun C H; Bradbury N A; Frizzell R A (September 2000). "E3KARP mediates the association of ezrin and protein kinase A with the cystic fibrosis transmembrane conductance regulator in airway cells". J. Biol. Chem. UNITED STATES. 275 (38): 29539–46. doi:10.1074/jbc.M004961200. ISSN0021-9258. PMID10893422.
↑Hwang, J I; Heo K; Shin K J; Kim E; Yun C; Ryu S H; Shin H S; Suh P G (June 2000). "Regulation of phospholipase C-beta 3 activity by Na+/H+ exchanger regulatory factor 2". J. Biol. Chem. UNITED STATES. 275 (22): 16632–7. doi:10.1074/jbc.M001410200. ISSN0021-9258. PMID10748023.
Yun CH, Lamprecht G, Forster DV, Sidor A (1998). "NHE3 kinase A regulatory protein E3KARP binds the epithelial brush border Na+/H+ exchanger NHE3 and the cytoskeletal protein ezrin". J. Biol. Chem. 273 (40): 25856–63. doi:10.1074/jbc.273.40.25856. PMID9748260.
Imai K, Sarker AH, Akiyama K, et al. (1999). "Genomic structure and sequence of a human homologue (NTHL1/NTH1) of Escherichia coli endonuclease III with those of the adjacent parts of TSC2 and SLC9A3R2 genes". Gene. 222 (2): 287–95. doi:10.1016/S0378-1119(98)00485-5. PMID9831664.
Zizak M, Lamprecht G, Steplock D, et al. (1999). "cAMP-induced phosphorylation and inhibition of Na(+)/H(+) exchanger 3 (NHE3) are dependent on the presence but not the phosphorylation of NHE regulatory factor". J. Biol. Chem. 274 (35): 24753–8. doi:10.1074/jbc.274.35.24753. PMID10455146.
Hwang JI, Heo K, Shin KJ, et al. (2000). "Regulation of phospholipase C-beta 3 activity by Na+/H+ exchanger regulatory factor 2". J. Biol. Chem. 275 (22): 16632–7. doi:10.1074/jbc.M001410200. PMID10748023.
Sun F, Hug MJ, Lewarchik CM, et al. (2000). "E3KARP mediates the association of ezrin and protein kinase A with the cystic fibrosis transmembrane conductance regulator in airway cells". J. Biol. Chem. 275 (38): 29539–46. doi:10.1074/jbc.M004961200. PMID10893422.
Yun CC, Chen Y, Lang F (2002). "Glucocorticoid activation of Na(+)/H(+) exchanger isoform 3 revisited. The roles of SGK1 and NHERF2". J. Biol. Chem. 277 (10): 7676–83. doi:10.1074/jbc.M107768200. PMID11751930.
DeMarco SJ, Chicka MC, Strehler EE (2002). "Plasma membrane Ca2+ ATPase isoform 2b interacts preferentially with Na+/H+ exchanger regulatory factor 2 in apical plasma membranes". J. Biol. Chem. 277 (12): 10506–11. doi:10.1074/jbc.M111616200. PMID11786550.
Ingraffea J, Reczek D, Bretscher A (2002). "Distinct cell type-specific expression of scaffolding proteins EBP50 and E3KARP: EBP50 is generally expressed with ezrin in specific epithelia, whereas E3KARP is not". Eur. J. Cell Biol. 81 (2): 61–8. doi:10.1078/0171-9335-00218. PMID11893083.
Kim JH, Lee-Kwon W, Park JB, et al. (2002). "Ca(2+)-dependent inhibition of Na+/H+ exchanger 3 (NHE3) requires an NHE3-E3KARP-alpha-actinin-4 complex for oligomerization and endocytosis". J. Biol. Chem. 277 (26): 23714–24. doi:10.1074/jbc.M200835200. PMID11948184.
Li Y, Li J, Straight SW, Kershaw DB (2002). "PDZ domain-mediated interaction of rabbit podocalyxin and Na(+)/H(+) exchange regulatory factor-2". Am. J. Physiol. Renal Physiol. 282 (6): F1129–39. doi:10.1152/ajprenal.00131.2001. PMID11997330.
Sitaraman SV, Wang L, Wong M, et al. (2002). "The adenosine 2b receptor is recruited to the plasma membrane and associates with E3KARP and Ezrin upon agonist stimulation". J. Biol. Chem. 277 (36): 33188–95. doi:10.1074/jbc.M202522200. PMID12080047.
Lamprecht G, Heil A, Baisch S, et al. (2002). "The down regulated in adenoma (dra) gene product binds to the second PDZ domain of the NHE3 kinase A regulatory protein (E3KARP), potentially linking intestinal Cl-/HCO3- exchange to Na+/H+ exchange". Biochemistry. 41 (41): 12336–42. doi:10.1021/bi0259103. PMID12369822.