Requirement of Negative Residues, Asp 95 and Asp 105, in S2 on Membrane Integration of a Voltage-dependent K[sup +] Channel, KAT1.

Identifies the negative residues of the second transmembrane segment in the plant voltage-dependent K[sup+] channel, KAT1, which involves the function of voltage sensing. Failure of point mutations at D95 and D105 to complement the K[sup+] uptake deficient properties of the mutant yeast; Role played by both residues in the membrane topogenesis of the voltage sensor KAT1.