Cilia in the brain display region-dependent oscillations of length and orientation
Fig 7
Correlation of cilia length and circular angle among various brain regions and relationship between cilia length/angle and network connectivity.
(A) Heatmap showing the correlation of cilia length (based on the mean of the section means) among different brain regions. The correlation coefficient ranges from 1 (indicating the most positive correlation, red) to −1 (indicating the most negative correlation, blue). Positive correlation implies that the cilia lengths in the two regions are on the longer and shorter side simultaneously. Negative correlation indicates that the two regions have opposite cilia length sizes; underlying data are available in S2 Data. (B) Heatmap displaying the correlation of cilia angle (based on the mean of the section circular means) among different brain regions. The correlation coefficient ranges from 1 (indicating the most positive correlation, purple) to −1 (indicating the most negative correlation, green); underlying data are available in S2 Data. (C) Anatomical network of the brain regions in our study. The network is embedded in 2D space using a spring embedding, in which highly connected nodes are pulled together as by a spring. Node size represents betweenness, a measurement of centrality based on the number of shortest paths between nodes that a particular node shows up on. Nodes are colored according to their community assignment, as determined by the Leiden algorithm. (D) Correlogram indicating the strength of input-output connections between all pairs of regions in the dataset. The color bar indicates the log-normalized projection density between any two regions. Regions are grouped according to their community membership. (E) Bar graph comparing projection strength between regions significantly correlated with cilia length vs. those not correlated. Projection strength equals the log normalization of normalized (by injection volume) projection density. (F) Fraction of region pairs significantly correlated by cilia length among all regions pairs between two communities. For example, a fraction of 0.111 means that 11.1% of all region pairs between the red and green communities are correlated by cilia length. (G) Bar graph comparing projection strength between regions significantly correlated with cilia angle versus those not correlated. (H) Fraction of region pairs significantly correlated by cilia angle among all regions pairs between two communities. (I) Cilia length correlation network. The spring embedding puts regions more highly correlated closer together. Betweenness and community membership are shown as node size and color, respectively. (J) Cilia length correlogram shows the groupings of different regions by community, as well as their correlation patterns. (K) Cilia angle correlation network. Betweenness and community membership are shown as node size and color, respectively. (L) Cilia angle correlogram shows the groupings of different regions by community, as well as their correlation patterns. Underlying data of Fig 7C-L are available in S2 Data, and from the publicly available Allen Mouse Brain Connectivity Atlas Data.