High impact information on DopR2

• DAMB, a novel dopamine receptor expressed specifically in Drosophila mushroom bodies [1].
• In situ hybridization and immunohistochemical analyses revealed highly enriched expression of DAMB in mushroom bodies, in a pattern coincident with the rutabaga-encoded adenylyl cyclase [1].
• The spatial coexpression of DAMB and the cyclase, along with DAMB's capacity to mediate dopamine-induced increases in cAMP make this receptor an attractive candidate for initiating biochemical cascades underlying learning [1].
• The DopR99B receptor maps to 99B3-5, close to the position of the octopamine/tyramine receptor gene at 99A10-B1, suggesting that the two may be related through a gene duplication [2].
• Agonist stimulation of DopR99B receptors expressed in Xenopus oocytes increased intracellular Ca2+ levels monitored as changes in an endogenous inward Ca2+-dependent chloride current [2].

Biological context of DopR2

• This pharmacological profile plus the second-messenger coupling pattern suggest that the DopR99B receptor is a D1-like dopamine receptor [2].
• However, the hydrophobic core region of the DopR99B receptor shows almost equal amino acid sequence identity (40-48%) with vertebrate serotonergic, alpha 1- and beta-adrenergic, and D1-like and D2-like dopaminergic receptors [2].

Analytical, diagnostic and therapeutic context of DopR2

• One new receptor, DAMB, was identified as a dopamine D1 receptor by sequence analysis and pharmacological characterization [1].
• Because DopR99B is the second dopamine receptor cloned from Drosophila, this work establishes dopamine receptor diversity in a system amenable to genetic dissection [2].

References