Fig. 3

Mxc is required for NB proliferation and cell fate maintenance. A Statistical analysis of the numbers of NBs at different developmental stages (96 and 120 hours AEL) in wt and mxc RNAi brain lobes. Dpn⁺ cells larger than 8µm in diameter were considered NBs [25]. The data are plotted as mean ± SD. ****p < 0.0001 using a Student’s t test, p = 2.555E–05 and 7.502E–06, respectively. Numbers of brain lobes counted N = 5, N = 5, N = 5, N = 6, respectively. B Statistics on nuclear Pros in the NBs in mxc RNAi larval central brain at various developmental stages of 48, 72, 96 and 120 hours AEL (After Eggs Laying). The data are plotted as mean ± SD. *p < 0.05 and ****p < 0.0001 using a Student’s t test, p = 0.0160 and 3.574E–06, respectively. Numbers of NBs counted N = 239, N = 112, N = 310, N = 740, respectively. C, D Third-instar larval brains containing Type-I NB FLP-out clones of wt (C) and mxc RNAi (D), labeled by anti-GFP (green), anti-Dpn (blue) and anti-Pros (red). Doted circles mark the location of the NBs. wt clone showing one large NB with dozens of small daughter cells (C). mxc RNAi clone showing one large NB and fewer daughter cells in one lineage (D). Scale bars: 10 µm. E Statistical analysis of the numbers of cells in each wt lineage and mxc RNAi lineage. The data are plotted as mean ± SD. ****p < 0.0001 using a Student’s t test, p = 3.620E-08. Numbers of clones counted N = 5, N = 11, respectively. F–G’ Third-instar larval brains of wt (F–F’) and mxc RNAi (G–G’), labeled by anti-Dpn (red), anti-Pros (green) and anti-PH3(blue). No differences of PH3 signals in NBs between wt (F) and mxc knockdown (G) were observed. Scale bars: 20 μm. H–I’ Z-axis projection of third-instar larval brains of wt (H–H’) and mxc RNAi (I–I’), labeled by EdU (red) and anti-Dpn (green). EdU was stained for 30 min. EdU signals were detected in wt central brain (H). Much less EdU signals were detected in mxc RNAi central brain (I). Scale bars: 20 μm