Activity-Dependent Gene Expression in the Mammalian Olfactory Epithelium.
Level 5 - mechanism / opinion, no new human data
Preclinical review and meta-analysis of animal transcriptomic datasets (Level 5 by Oxford CEBM criteria/analogy).
PubMed 28525560 · doi:10.1093/chemse/bjx028
What was done
The authors synthesized published literature and conducted a meta-analysis of existing transcriptomic datasets to identify activity-dependent mRNAs in the mammalian olfactory mucosa following experimental interventions that alter olfactory sensory neuron activity.
What was found
The meta-analysis identified 443 mRNAs that respond to methods that alter olfactory sensory neuron activity, with 350 of these expressed in mature olfactory sensory neurons. Many identified mRNAs encode proteins involved in presynaptic terminal function or electrical activity support. The analysis determined that poor agreement among published studies was largely caused by underpowered experiments and off-target effects, such as changes in sustentacular cell enzyme mRNAs (Cyp2a4 and Cyp2g1) following unilateral naris occlusion, while odorant receptor mRNAs showed poor consistency due to differences in expression frequency.
Why it matters
This synthesis clarifies the core set of activity-dependent transcripts linked to synaptic plasticity and electrical function in mature olfactory neurons while explaining the methodological sources of conflicting results across prior studies.
Limits
The abstract does not provide the total number of datasets or studies included. The findings reflect animal models rather than human clinical data. Primary studies were limited by low statistical power, off-target effects of sensory deprivation methods, and baseline expression frequency variations among odorant receptors.
Cited by
- supports The turnover and sensory tuning of olfactory neurons is activity-dependent, requiring electrical firing generated by sniffing and odor exposure.