Figure 5. Morphology and immunohistochemistry of the hippocampal dentate gyrus in wild-type and Gnb5-knockout mice.

The shape of the dentate gyrus in Gnb5 KO mice, in sections of hippocampus stained for calbindin-1 immunoreactivity and examined at 20X magnification, was found to be more circular and immature (A, C and E; cf. Fig. S3) than in wild-type littermates in which its shape was fuller and more elongated (B, D and F). Data shown are from three independent age-matched littermates. At 3 weeks there was no discernible visual difference in the dentate gyrus morphology between the Gnb5 KO mice (G) and their wild type littermates (H). Sections shown are representative of results from three age-matched littermates. At higher magnification (63X) in the Gnb5 KO mice, calbindin-1 positive neurons were found to be more disarranged and a significant number of ectopic cells were found outside the dentate gyrus layer (I) as compared to the wild type which were more organized (J). Hippocampal sections (20X) from Gnb5 KO mice (K) and their wild type littermates (L) were subdivided into multiple regions as shown to allow for quantitative histomorphometry using ImageJ software as described in the supplementary online methods. M. The thickness of the granule cell layer relative to the molecular layer was determined as described in the supplementary online methods. N. The number of ectopic calbindin-1 positive cells present in the molecular layer of the hippocampus in 1-week old wild-type or Gβ5-deficient mice was determined as described in the supplementary online methods. In M, N, n = 3 littermate pairs of wild-type and Gnb5 KO mice.