Mapping the expression of soluble olfactory proteins in the honeybee.
Chemical communication in insects is mediated by soluble binding proteins, belonging to two large families, Odorant-binding Proteins (OBPs) and Chemosensory Proteins (CSPs). Recently, evidence has been provided that OBPs are involved in recognition of chemical stimuli. We therefore decided to investigate the expression of OBPs and CSPs in the honeybee at the protein level, using a proteomic approach. Our results are in agreement with previous reports of expression at the RNA level and show that 12 of the 21 OBPs predicted in the genome of the honeybee Apis mellifera and 2 of the 6 CSPs are present in the foragers' antennae, while the larvae express only three OBPs and a single CSP. MALDI mass spectrometry on crude antennal extracts and MALDI profiling on sections of antennae demonstrated that these techniques can be applied to investigate individual differences in the expression of abundant proteins, such as OBPs and CSPs, as well as to detect the presence of proteins in different regions of the antenna. Finally, as part of a project aimed at the characterization of all OBPs and CSPs of the honeybee, we expressed 5 OBPs and 4 CSPs in a bacterial system and measured their affinity to a number of ligands. Clear differences in their binding spectra have been observed between OBPs, as well as CSPs.
Dani
Francesca Romana
FR
CISM, University of Firenze, Firenze, Italy.
Iovinella
Immacolata
I
Felicioli
Antonio
A
Niccolini
Alberto
A
Calvello
Maria Antonietta
MA
Carucci
Maria Giovanna
MG
Qiao
Huili
H
Pieraccini
Giuseppe
G
Turillazzi
Stefano
S
Moneti
Gloriano
G
Pelosi
Paolo
P
D000818:Animals; D001516:Bees / Q000235:genetics / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D020869:Gene Expression Profiling / Q000379:methods; D019476:Insect Proteins / Q000096:biosynthesis* / Q000145:classification / Q000235:genetics / Q000378:metabolism; D040901:Proteomics / Q000379:methods; D018035:Receptors, Odorant / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
D019476:Insect Proteins; D018035:Receptors, Odorant; C045648:odorant-binding protein