Fig. 2: Cep55-knockout mice show microcephaly.

a Brain images from P0 mice of the indicated genotypes. b Weights of the indicated organs and genotypes. Horizontal bars indicate mean; n = 3, 13, 5 (E18.5-brain); 11, 20, 12 (P0-brain); 4 and 4 (P0-lungs, liver, heart, and kidneys); 5, 20, and 5 (E18.5-body without (w/o) brain) mice, respectively; P-values calculated using one-way ANOVA followed by Dunnett’s multiple comparisons test where more than two sets of data are compared, otherwise Student’s two-tailed unpaired t-test. c Western blot of protein extracts from brain cortices of the indicated genotypes and developmental stages with antibodies against Cep55 and Actin; n = 3 independent experiments. d Sagittal sections of P0 brains stained with hematoxylin and eosin (HE). Dotted black lines indicate cortical dimensions measured in e (curved) and f (straight). Dotted red boxes indicate area enlarged in g. e, f Quantification of cortical length (e) and cortical thickness (f) at the indicated developmental stages. Control includes Cep55^+/+ and Cep55^+/− mice. n = 3 mice per genotype. g Enlarged view of the forebrain cortices from d. CP, cortical plate; IZ, intermediate zone; VZ, ventricular zone. h Cell counts in a 200 µm-wide field of neocortex in control and Cep55^−/− mice. n = 3 mice per genotype. e, f, h Horizontal bars indicate mean; error bars indicate SEM; P-values calculated using Student’s two-tailed unpaired t-test. a–g Cep55^−/− indicates Cep55^tm1a/tm1a mice (see Fig. 1a for allele details). Source data for b, c, e, f, h are provided as a Source Data file.