Related Experiment Videos
Conformational isomers of insect odorant-binding proteins
Zhang Deyu1, Walter Soares Leal
1Laboratory of Chemical Prospecting, National Institute of Agriobiological Sciences, 1-2 Ohwashi, Tsukuba, 305-8634, Japan.
Archives of Biochemistry and Biophysics
|December 19, 2001
Summary
Researchers identified two odorant-binding proteins (OBPs) in two chafer beetle species. One OBP type resembles pheromone-binding proteins, while the other exists in distinct forms, suggesting conformational differences in insect olfaction.
Area of Science:
- Entomology
- Molecular Biology
- Biochemistry
Background:
- Odorant-binding proteins (OBPs) play crucial roles in insect chemoreception.
- Scarab beetles, like the large black chafer (Holotrichia parallela) and yellowish elongate chafer (Heptophylla picea), rely on olfaction for various behaviors.
Purpose of the Study:
- To identify and characterize odorant-binding proteins (OBPs) in Holotrichia parallela and Heptophylla picea.
- To investigate the structural and potential functional differences between OBPs within these species.
Main Methods:
- cDNA cloning and sequencing to identify OBP genes.
- Native gel electrophoresis to analyze protein migration and identify distinct forms.
- Amino acid sequence analysis to determine protein identity and conserved residues.
Main Results:
- Two distinct OBPs were identified in both H. parallela and H. picea.
- One OBP (OBP1) showed high sequence identity (>88%) to known pheromone-binding proteins (PBPs) in scarab beetles, featuring 116 amino acids and six conserved cysteines.
- The second OBP (OBP2) from each species separated into two bands on native gels, indicating conformational isomers, despite sequencing revealing only a single gene product. These OBPs have 133 amino acids with conserved cysteines.
Conclusions:
- The identified OBPs in H. parallela and H. picea contribute to our understanding of insect olfactory mechanisms.
- The presence of PBP-like proteins suggests a role in pheromone detection, while the conformational isomers of OBP2 may indicate specialized functions or ligand-binding properties.