NHERF2 protein mobility rate is determined by a unique C-terminal domain that is also necessary for its regulation of NHE3 protein in OK cells

Jianbo Yang, Varsha Singh, Boyoung Cha, Tian E. Chen, Rafiquel Sarker, Rakhilya Murtazina, Shi Jin, Nicholas C. Zachos, George H. Patterson, C. Ming Tse, Olga Kovbasnjuk, Xuhang Li, Mark Donowitz

Research output: Contribution to journalArticlepeer-review

10 Scopus citations


Na+/H+ exchanger regulatory factor (NHERF) proteins are a family of PSD-95/Discs-large/ZO-1 (PDZ)-scaffolding proteins, three of which (NHERFs 1-3) are localized to the brush border in kidney and intestinal epithelial cells. All NHERF proteins are involved in anchoring membrane proteins that contain PDZ recognition motifs to form multiprotein signaling complexes. In contrast to their predicted immobility, NHERF1, NHERF2, and NHERF3 were all shown by fluorescence recovery after photo-bleaching/ confocal microscopy to be surprisingly mobile in the microvilli of the renal proximal tubule OK cell line. Their diffusion coefficients, although different among the three, were all of the same magnitude as that of the transmembrane proteins, suggesting they are all anchored in the microvilli but to different extents. NHERF3 moves faster than NHERF1, and NHERF2 moves the slowest. Several chimeras and mutants of NHERF1 and NHERF2 were made to determine which part of NHERF2 confers the slower mobility rate. Surprisingly, the slower mobility rate of NHERF2 was determined by a unique C-terminal domain, which includes a nonconserved region along with the ezrin, radixin, moesin (ERM) binding domain. Also, this C-terminal domain of NHERF2 determined its greater detergent insolubility and was necessary for the formation of larger multiprotein NHERF2 complexes. In addition, this NHERF2 domain was functionally significant in NHE3 regulation, being necessary for stimulation by lysophosphatidic acid of activity and increased mobility of NHE3, as well as necessary for inhibition of NHE3 activity by calcium ionophore 4-Br-A23187. Thus, multiple functions of NHERF2 require involvement of an additional domain in this protein.

Original languageEnglish (US)
Pages (from-to)16960-16974
Number of pages15
JournalJournal of Biological Chemistry
Issue number23
StatePublished - Jun 7 2013

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology


Dive into the research topics of 'NHERF2 protein mobility rate is determined by a unique C-terminal domain that is also necessary for its regulation of NHE3 protein in OK cells'. Together they form a unique fingerprint.

Cite this