Dear Trygve @trygveb,
I was wondering if in snRNAseq one should be able to detect proliferating cells in CNS at their expected frequencies. If in the actively proliferating cells there are no nuclear envelopes, would that mean that such cells will be detected as debris in snRNAseq? Do you expect to not have such artifact in scRNAseq?
I searched for MKI67+ marker in several snRNAseq and only saw very small fraction of such cells. I know, one won’t expect neurons to be proliferative in adult human brain, but some glia, for instance, should be proliferative.
Good point. If the nuclear envelope has broken down, then I expect that those nuclei would be excluded from the data set. MKI67 should be expressed throughout mitosis, and we should detect it in a subset of proliferating cells. As you noted, these cells are exceedingly rare in human cortex, although more common in mouse cortex: http://celltypes.brain-map.org/rnaseq/mouse/cortex-and-hippocampus