title: Characterization of the two distinct subtypes of metabotropic glutamate receptors from honeybee, Apis mellifera.
abstract: L-Glutamate is a major neurotransmitter at the excitatory synapses in the vertebrate brain. It is also the excitatory neurotransmitter at neuromuscular junctions in insects, however its functions in their brains remain to be established. We identified and characterized two different subtypes (AmGluRA and AmGluRB) of metabotropic glutamate receptors (mGluRs) from an eusocial insect, honeybee. Both AmGluRA and AmGluRB form homodimers independently on disulfide bonds, and bind [3H]glutamate with K(D) values of 156.7 and 80.7 nM, respectively. AmGluRB is specifically expressed in the brain, while AmGluRA is expressed in the brain and other body parts, suggesting that AmGluRA is also present at the neuromuscular junctions. Both mGluRs are expressed in the mushroom bodies and the brain regions of honeybees, where motor neurons are clustered. Their expression in the brain apparently overlaps, suggesting that they may interact with each other to modulate the glutamatergic neurotransmission.
authors.affiliation: Department of Applied Biological Sciences, School of Agricultural Sciences, Nagoya University, Chikusa, Nagoya, 464-8601, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Funada
authors.forename: Shinobu
authors.initials: S
authors.lastname: Yasuo
authors.forename: Takashi
authors.initials: T
authors.lastname: Yoshimura
authors.forename: Shizufumi
authors.initials: S
authors.lastname: Ebihara
authors.forename: Hiromi
authors.initials: H
authors.lastname: Sasagawa
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Kitagawa
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Kadowaki
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001516:Bees / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D001921:Brain / Q000378:metabolism*; D020869:Gene Expression Profiling / Q000379:methods*; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010802:Phylogeny; D018094:Receptors, Metabotropic Glutamate / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000378:metabolism*
chemical_list: D018094:Receptors, Metabotropic Glutamate