Periodic Reporting for period 1 - SUBNETVIS (Identifying subtype specific networks involved in sensory representation in mouse primary visual cortex)
Período documentado: 2020-04-01 hasta 2022-03-31
To this aim we defined the following objectives:
1) Develop a method to study the in vivo properties of fine neuronal subtypes
2) Determine whether these diverse neuronal subtypes have diverse activity patterns in vivo
3) Describe the visual properties of these fine neuronal subtypes
4) Link these visual properties to their connectivity patterns
We found that the visual properties of inhibitory neurons in the primary visual cortex differed greatly between the major Families (Pvalb, Sst, Vip, Sncg and Lamp5). However, the fine subtypes composing these Families of inhibitory cells shared very similar visual responses. In sharp contrast, the modulation by the animal’s state greatly varied even between fine subtypes of the same Family. Strikingly, we found that a single axis of variability, defined using only gene expression, could predict this state modulation across all subtypes we have recorded from. This single axis also correlated with the spike properties of the subtypes as well as with their morphology. These results were collected and published online in a pre-print article (doi: https://doi.org/10.1101/2021.10.24.465600) which was presented at different international conferences (COSYNE, FENS forum, SfN annual meeting) and has just been accepted in principle for publication by the peer-reviewed journal Nature.
We are currently still exploring how the connectivity of these fine subtypes can determine their tuning properties. In particular, we are using retrograde tracing to decipher whether excitatory cells with different modulation by the animal’s arousal are connected by diverse neuronal subtypes and how this relates with their in vivo properties.
More generally, subtype-specific disfunctions have been involved in several brain disorders, and fine tuning of inhibition in cortex is critical to maintain proper brain function. Our method and our results will support future studies exploring the involvement of these fine subtypes in brain disorders.