title: Expressed sequence tags from cephalic chemosensory organs of the northern walnut husk fly, Rhagoletis suavis, including a putative canonical odorant receptor.
abstract: Rhagoletis fruit flies are important both as major agricultural pests and as model organisms for the study of adaptation to new host plants and host race formation. Response to fruit odor plays a critical role in such adaptation. To better understand olfaction in Rhagoletis, an expressed sequence tag (EST) study was carried out on the antennae and maxillary palps of Rhagoletis suavis (Loew) (Diptera: Tephritidae), a common pest of walnuts in eastern United States. After cDNA cloning and sequencing, 544 ESTs were annotated. Of these, 66% had an open reading frame and could be matched to a previously sequenced gene. Based on BLAST sequence homology, 9% (49 of 544 sequences) were nuclear genes potentially involved in olfaction. The most significant finding is a putative odorant receptor (OR), RSOr1, that is homologous to Drosophila melanogaster Or49a and Or85f. This is the first tephritid OR discovered that might recognize a specific odorant. Other olfactory genes recovered included odorant binding proteins, chemosensory proteins, and putative odorant degrading enzymes.
authors.affiliation: Department of Entomology, University of Illinois at Urbana-Champaign, 320 Morrill Hall, 505 S. Goodwin Ave., Urbana, IL 61801, USA. ramsdell@life.uiuc.edu
authors.forename: Karlene M M
authors.initials: KM
authors.lastname: Ramsdell
authors.forename: Sheila A
authors.initials: SA
authors.lastname: Lyons-Sobaski
authors.forename: Hugh M
authors.initials: HM
authors.lastname: Robertson
authors.forename: Kimberly K O
authors.initials: KK
authors.lastname: Walden
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Feder
authors.forename: Kevin
authors.initials: K
authors.lastname: Wanner
authors.forename: Stewart H
authors.initials: SH
authors.lastname: Berlocher
mesh_terms: D000818:Animals; D004175:Diptera / Q000502:physiology*; D020224:Expressed Sequence Tags; D005786:Gene Expression Regulation / Q000502:physiology*; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D018035:Receptors, Odorant / Q000235:genetics / Q000378:metabolism*; D012679:Sense Organs / Q000502:physiology*; D012903:Smell / Q000502:physiology
chemical_list: D019476:Insect Proteins; D018035:Receptors, Odorant