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Real-time In Vitro Monitoring of Odorant Receptor Activation by an Odorant in the Vapor Phase
Published on: April 23, 2019
Odorant Receptors Containing Conserved Amino Acid Sequences in Transmembrane Domain 7 Display Distinct Expression
Sang Eun Ryu1, Tammy Shim1, Ju-Yeon Yi1
1Department of Cognitive and Brain Sciences, Graduate school, Daegu Gyeongbuk Institute of Science & Technology (DGIST), Daegu 42988, Korea.
Researchers identified a conserved 18 amino acid motif (CAS-TM7) in odorant receptors. This motif shows specific expression patterns in the olfactory system and non-olfactory tissues, suggesting broader physiological roles beyond olfaction.
Area of Science:
- Genomics
- Molecular Biology
- Neuroscience
Background:
- Mammalian genomes are well-characterized, with conserved regions in odorant receptors (ORs) distinct from other G-protein coupled receptors.
- While many conserved motifs exist, not all have been functionally characterized.
- The CAS-TM7 motif in transmembrane domain seven is a newly identified conserved sequence in ORs.
Purpose of the Study:
- To identify and characterize a highly conserved 18 amino acid sequence motif (CAS-TM7) within transmembrane domain seven of odorant receptors.
- To investigate the expression pattern and distribution of the CAS-TM7 motif across various odorant receptors.
- To explore the potential broader physiological roles of this conserved motif.
Main Methods:
- Sequence alignment of odorant receptor sequences to identify conserved motifs.
- Development and utilization of a sequence-specific peptide antibody against CAS-TM7 for protein localization.
- Confirmation of antibody specificity in both in vitro and in vivo (rat) systems.
- Analysis of CAS-TM7 odorant receptor localization within the olfactory epithelium and olfactory bulb.
Main Results:
- The CAS-TM7 motif was identified as a highly conserved 18 amino acid sequence in transmembrane domain seven of odorant receptors.
- A specific antibody confirmed CAS-TM7 odorant receptor localization in distinct patterns across the olfactory epithelium (septum, endoturbinate, ectoturbinate).
- CAS-TM7 odorant receptors were primarily localized to the dorsal olfactory bulb, mirroring olfactory epithelium patterns, and ectopically expressed in non-olfactory tissues in humans and rats.
Conclusions:
- The study successfully characterized the expression patterns of odorant receptors containing the CAS-TM7 motif.
- The conserved CAS-TM7 motif exhibits specific localization patterns within the olfactory system and non-olfactory tissues.
- This conserved motif may play critical roles in physiological functions beyond olfaction, indicating evolutionary conservation.
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