Figure 3. Inducible AT2-Specific Deletion of Dlk1 Fails to Affect AT2 Proliferation after PA Injury.

(A) Schematic of inducible AT2 cell-specific deletion of Dlk1 combined with Tomato lineage tracing (Dlk1^ΔAT2). The Tam-inducible SpC-CreER system was used to generate Dlk1^ΔAT2 mice. Cre expressed from the Sp-C promoter also deletes the “stop” sequence to allow mutant cells and their progeny to be labeled by Tomato.

(B) Tomato⁺ AT2 isolated by flow-sorting from Tam-treated control (WT) and Dlk1^ΔAT2 mice (Dlk1^del) without PA or at 3 and 7 days post PA were analyzed for Dlk1 expression by western blotting. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was used as a loading control. The relative band intensity of Dlk1 versus GAPDH was plotted, *p < 0.05.

(C and D) AT2 were isolated for qRT-PCR analysis. The relative expression of the proliferation markers CDC25C (C) and CLNB1 (D) in 3-day post-injury AT2 were compared with WT controls.

(E) Western blot of the proliferation marker phospho-histone H3 3 days post-injury in Dlk1^del and control AT2. Quantification of western blots was performed using ImageJ.

All bar graph data are presented as mean ± SE; n ≥ 3. See also Figures S3 and S4.