Neurotransmitter receptors on taste bud cells (TBCs) and taste nerve fibres are likely to contribute to taste transduction by mediating the interaction among TBCs and that between TBCs and taste nerve fibres. We investigated the functional expression of P2 receptor subtypes on TBCs of mouse fungiform papillae. Electrophysiological studies showed that 100 µM ATP applied to their basolateral membranes either depolarized or hyperpolarized a few cells per taste bud. Ca²⁺-imaging showed that similarly applied 1 µM ATP, 30 µM BzATP (a P2X₇ agonist), or 1 µM 2MeSATP (a P2Y₁ and P2Y₁₁ agonist) increased intracellular Ca²⁺ concentration, but 100 µM UTP (a P2Y₂ and P2Y₄ agonist) and , -meATP (a P2X agonist except for P2X₂, P2X₄, and P2X₇) did not. RT-PCR suggested the expression of P2X₂, P2X₄, P2X₇, P2Y₁, P2Y₁₃, and P2Y₁₄ among the seven P2X subtypes and seven P2Y subtypes examined. Immunohistostaining confirmed the expression of P2X₂. The exposure of the basolateral membranes to 3 mM ATP for 30 min caused the uptake of Lucifer Yellow CH in a few TBCs per taste bud. This was antagonized by 100 µM PPADS (a non-selective P2 blocker) and 1 µM KN-62 (a P2X₇ blocker). These results showed for the first time the functional expression of P2X₂ and P2X₇ on TBCs. The roles of P2 receptor subtypes in the taste transduction, and the renewal of TBCs, are discussed.