We have some generalized physical understanding of how ion channels interact with surrounding lipids but lack detailed descriptions on how interactions of particular amino acid with contacting lipids may regulate gating. Here we show a structure-specific interaction between an amino acid and inner-leaflet lipid that governs the gating transformations of TRPV4 (Transient Receptor Potential Vanilloid type 4). Many cation channels use a S4-S5 linker to transmit stimuli to the gate. At the start of TRPV4's linker helix is leucine 596. A hydrogen bond between L596's backbone oxygen and the indole of W733 of the TRP helix acts as a latch to maintain channel closure. The side chain of L596 interacts with the inner lipid leaflet near the polar-nonpolar interface in our model - an interaction that we explored by mutagenesis. We examined the outward currents of TRPV4-expressing Xenopus oocyte upon depolarizations as well as phenotypes of expressing yeast cells. Maintaining its hydrophobicity, L596F and L596V channels appear normal in gating. However, making this residue less hydrophobic (L596A, G, W, Q, K) reduces open probability (Po) (loss-of-function, LOF), likely due to altered interactions at the polar-nonpolar interface. L596I raises Po (gain-of-function, GOF), apparently by placing its methyl group closer to the polar region and receiving stronger water repulsion. Molecular dynamics simulations showed that the distance between the β carbons of H-bonded residues 596 and 733 is shortened in the LOFs and lengthened in the GOFs, strengthening or weakening the linker/TRP-helix latch respectively. These results highlight that, in each lipid-exposed focus, the L596-lipid attraction counteracts the latch bond in a tug-of-war to tune the Po of TRPV4.