Figure 3.

Pipette feeding of tamoxifen can induce CreERT2 activation dose‐dependently. (a) Representative confocal images showing T^CreERT2 lineage tracing in a subset of neuroepithelial and mesodermal cells 24 h following administration of 1 mg or 10 mg tamoxifen to the mother. Dashed lines indicate the regions quantified in B, scale bar = 100 μm. (b) CreERT2 was activated by pipette‐fed tamoxifen in neuromesodermal progenitor cells, which lineage trace a subset of PNP neuroepithelial cells, using two lineage‐selective Cre drivers 24 h before embryos were collected. T ^CreERT2 was activated with the indicated doses and Nkx1.2 ^CreERT2 produced comparable recombination when activated with 10 mg tamoxifen. * p < .05, each point represents an individual embryo (1 mg and 10 mg were from four litters, 2.5 mg and 5 mg were from 2 litters).