Expression of a carrot phenylalanine ammonia-lyase (PAL) gene (gDcPAL1) in suspension-cultured carrot cells is induced by dilution of the culture or by application of a fungal elicitor, as well as by ultraviolet B (UVB) irradiation. We demonstrated that among its upstream cis-elements (Takeda et al. [1997] Photochem. Photobiol. 66, 464–470), L₄ is UVB responsive, and L₁ is protoplastization- (dilution-) and elicitor responsive, from studies with transiently transformed mutated or truncated gDcPAL1 promoter–luc constructs. This conclusion is consistent with our observation that PAL activities induced by UVB and by protoplastization (dilution) or elicitor are additive.