Nunghathai SawasdeeMutita JunkingPiengpaga NgaojanlarNattakan SukomonDuangporn UngsupravateThawornchai LimjindapornVaraporn AkkarapatumwongSansanee NoisakranPa Thai YenchitsomanusMahidol UniversityInstitute of Molecular Biosciences2018-09-242018-09-242010-10-08Biochemical and Biophysical Research Communications. Vol.401, No.1 (2010), 85-91109021040006291X2-s2.0-77957655308https://repository.li.mahidol.ac.th/handle/20.500.14594/28619Kidney anion exchanger 1 (kAE1) mediates chloride (Cl-) and bicarbonate (HCO3-) exchange at the basolateral membrane of kidney α-intercalated cells. Impaired trafficking of kAE1 leads to defect of the Cl-/HCO3-exchange at the basolateral membrane and failure of proton (H+) secretion at the apical membrane, causing a kidney disease - distal renal tubular acidosis (dRTA). To gain a better insight into kAE1 trafficking, we searched for proteins physically interacting with the C-terminal region of kAE1 (Ct-kAE1), which contains motifs crucial for intracellular trafficking, by a yeast two-hybrid (Y2H) system. An adaptor-related protein complex 1 μ1A (AP-1 mu1A) subunit was found to interact with Ct-kAE1. The interaction between either Ct-kAE1 or full-length kAE1 and AP-1 mu1A were confirmed in human embryonic kidney (HEK) 293T by co-immunoprecipitation, affinity co-purification, co-localization, yellow fluorescent protein (YFP)-based protein fragment complementation assay (PCA) and GST pull-down assay. The interacting site for AP-1 mu1A on Ct-kAE1 was found to be Y904DEV907, a subset of YXXØ motif. Interestingly, suppression of endogenous AP-1 mu1A in HEK 293T by small interfering RNA (siRNA) decreased membrane localization of kAE1 and increased its intracellular accumulation, suggesting for the first time that AP-1 mu1A is involved in the kAE1 trafficking of kidney α-intercalated cells. © 2010 Elsevier Inc.Mahidol UniversityBiochemistry, Genetics and Molecular BiologyArticleSCOPUS10.1016/j.bbrc.2010.09.015