Regulation of ClC-2 Activity by SPAK and OSR1

• DOI: 10.1159/000355816
• Publication Date: 2014-10-15T06:59:59Z
• Authors: Jamshed Warsi; Zohreh Hosseinzadeh; Bernat Elvira; Rosi Bissinger; Ekaterina Shumilina; Florian Lang
• Keywords: Patch-Clamp Techniques; Dermatology; Protein Serine-Threonine Kinases; WNK; Minor Histocompatibility Antigens; Xenopus laevis; 03 medical and health sciences; Cl- channels; WNK Lysine-Deficient Protein Kinase 1; Chloride Channels; Diseases of the circulatory (Cardiovascular) system; Animals; Humans; Voltage clamp; Protein Synthesis Inhibitors; 0303 health sciences; Brefeldin A; Cell Membrane; Intracellular Signaling Peptides and Proteins; Diseases of the genitourinary system. Urology; CLC-2 Chloride Channels; RL1-803; RC666-701; Oocytes; Cell volume regulation; RC870-923

<b><i>Background/Aims: </i></b>SPAK (SPS1-related proline/alanine-rich kinase) and OSR1 (oxidative stress-responsive kinase 1) are powerful regulators of diverse transport processes. Both kinases activated by cell shrinkage participate in stimulation regulatory volume increase (RVI). Execution RVI involves inhibition Cl<sup>-</sup> channels. The present study explored whether SPAK and/or regulate the activity channel ClC-2. <b><i>Methods: </i></b>To this end, ClC-2 was expressed <i>Xenopus laevis</i> oocytes with or without additional expression wild type SPAK, constitutively active SPAK<sup>T233E</sup>, WNK1 insensitive inactive SPAK<sup>T233A</sup>, catalytically SPAK<sup>D212A</sup>, OSR1, OSR1<sup>T185E</sup>, OSR1<sup>T185A</sup>, OSR1<sup>D164A</sup>. determined dual electrode voltage clamp. <b><i>Results: </i></b>Expression followed appearance a conductance (G<sub>Cl</sub>), which significantly decreased following coexpression wild-type but not Inhibition insertion brefeldin A (5 μM) resulted decline G<sub>Cl</sub> similar absence presence suggesting that did accelerate retrieval protein from membrane. <b><i>Conclusion: negative