Characterization of a Histidine Rich Cluster of Amino Acids in the Cytoplasmic Domain of the Na+/H+ Exchanger. Issue 3 (June 2000)

• Record Type: Journal Article
• Authors: Dibrov, Pavel; Murtazina, Rakhilya; Kinsella, James; Fliegel, Larry
• Is Part Of: Bioscience reports. Volume 20:Issue 3(2000)
• Page Start: 185
• Page End: 197
• Publication Date: 2000-06
• Subjects: Na+/H+ exchanger -- proton sensing -- histidine residues; Molecular biology -- Periodicals; Cytology -- Periodicals; 572.8
• DOI: 10.1023/A:1005567519792
• Languages: English
• ISSNs: 0144-8463

Abstract

Abstract : We examined the function of a highly conserved Histidine rich sequence ofamino acids found in the carboxyl-terminal of the Na + /H + exchanger (NHE1). A fusion protein containing the sequenceHYGHHH (540–545) and the balance of the carboxyl terminalof the protein did not bind calcium but bound to an immobilizedmetal affinity column and could be used to partially purify theexchanger protein. Mutation of the sequence to either HYGAAA orHYGRRR did not affect activity of the intact protein. Mutationto HHHHHH did not affect proton activation of the Na+/H+exchanger or localization but caused a decreased maximal velocitysuggesting that this conserved sequence is important in maximalactivity of the Na + /H + exchanger.