Tag:iLEXY(N414L) is a light-regulated nuclear export signal sequence that consists of the LOV2 domain of the Avena sativa Phototropin 1 (PT1) gene, including the C-terminal Jα-helix and LOV core domain, in which the C-terminal Jα-helix has been converted into an artificial nuclear export sequence (NES). In the dark, the NES is tightly packed against the LOV core and is thus inactive. Upon illumination with blue light, the Jα-helix unfolds, exposing the NES, and allowing export from the nucleus of a protein of interest to which Tag:iLEXY(N414L) is fused. Tag:iLEXY(N414L) was derived by mutagenesis of Tag:LEXY; it contains an additional N414L amino acid substitution that increases the half time of LOV2 domain recovery in the dark in vitro, resulting in Tag:iLEXY(N414L) being a slow-cycling variant compared to Tag:LEXY (FBrf0250332).