Fig. 5: Follower is a transcriptional ground state of pLL progenitors.
From: Axon targeting of transcriptionally distinct pioneer neurons is regulated by retinoic acid signaling
A UMAP plot of all cells derived from 14, 18, 22, 30, and 48 hpf neurod1:egfp embryos. Major cell types are indicated. B UMAP of the pLL progenitors, pioneers, and followers. C, D Feature plots showing neurogenesis marker, neurog1, and neural differentiation marker, snap25b. E Trajectory inference plot showing the predicted differentiation trajectory, consistent with the expression patterns of neurogenesis and differentiation markers in (C, D). F UMAP plot of pLL progenitors, pioneers, and followers grouped by timepoint. The pLL cell counts at each timepoint are as follows: 14 hpf, 23 cells; 18 hpf, 167 cells; 22 hpf, 67 cells; 30 hpf, 340 cells; and 48 hpf, 50 cells. G, H Pioneer markers rpz5 and ret are predominantly expressed in pioneers, but not in progenitors. I, J Follower markers hoxb5a and zfhx3 are expressed in both progenitor and follower populations. K, L Feature plots showing coexpression of pioneer (ret or ntrk1) and follower (zfhx3 or nr2f2) genes during differentiation (14–22 hpf). Note that a subset of cells coexpress both pioneer and follower markers at these stages (white cells): 25 cells co-express ret and zfhx3, and 25 cells co-express ntrk1 and nr2f2. Low expression cut off is set at 3 UMI per cell. M, N Gene signature plots of cells between 14 and 22 hpf. The follower gene signature is present broadly at earlier stages, while the pioneer gene signature is strongest in cells from 22 hpf. O Gene expression over time as cells differentiate from progenitors to followers or pioneers. Note that follower gene expression is similar across stages, whereas pioneer genes are upregulated during later differentiation stages.
