Anxiety behaviors are affected in juvenile Gli2+/- and Gli3+/𝛥;699 mutant miceGli3+/𝛥;;699 mutant mice
Anthony Auger, PhD, Joan Jorgensen, DVM, Rithika Nurani, BSc, Wade Bushman, MD, Walid Farhat, MD.
University of Wisconsin, Madison, WI, USA.
BackgroundDysregulation of the hedgehog (Hh)-transcription factors, GLI2 and GLI3, are known to impact both urogenital and brain development; however, their influence on development of juvenile social and anxiety-like behavior is less clear. As compound mutation of Gli2+/-;Gli3+/𝛥;699 in mice exhibited a spectrum of urogenital malformations, we hypothesize that the degree of urogenital malformation will be associated with changes in juvenile social and anxiety-like behavior in Gli2+/- and Gli3+/𝛥;699 mutant mice. MethodsPostnatal day 25-26 (juvenile) male (n=12) and female (n=10) Gli2+/- mutant and control mice (male n=11; female n=10) , as well as male (n=10) and female (n=11) Gli3+/𝛥;699 mutant and control mice (male n=10; female n=10) were evaluated for social interaction, play, and anxiety behaviors over 3 days. Social investigation was measured during a 5-minute test as time spent grooming, sniffing, or following a test stimulus mouse. Rudimentary play-like behavior was assessed by measuring a "jerk and run" series of behaviors that is not goal directed alongside another mouse. Anxiety behavior was tested by placing individual mice in an open field arena for 30 minutes. Automated detection of overall movement via photo beam interruption and time in the center vs. surroundings were recorded. The following day, mice were euthanized, perfused with fixative for brain collection, and anogenital distances (AGD) were recorded. ResultsAs expected, AGD measurements were greater in males versus females (p < 0.001) in both Gli2+/- and Gli3+/𝛥;699 mice; however, we did not detect any influence of genotype. No significant differences of genotype were observed for juvenile play-like behavior or juvenile social interaction. Notably however, a significant impact of genotype on juvenile anxiety-like behavior was seen. In Gli2 mice, a two-way ANOVA analysis indicated a main effect of biological sex (p = 0.035) and an interaction of biological sex and genotype (p < 0.001). A Tukey post hoc comparison test indicated that Gli2+/- males exhibited decreased anxiety-like behavior compared to Gli2+/- females (p < 0.001) and wild type male controls (p < 0.001). In Gli3 mice, a two-way ANOVA analysis indicated a main effect of biological sex (p = 0.025), with male and female Gli3+/𝛥;699 mice exhibiting increased anxiety-like behavior compared to male and female wild type controls.
ConclusionsOur studies are the first to show possible association of altered anxiety-like behavior in mice with genetic disruption of Hh-GLI signaling, a pivotal pathway in genitourinary development. As disruption of Gli2 and Gli3 functioning did not alter AGD, it is possible that the consequences of these mutations were independent of hormonal dysfunction. While GLI2 and GLI3 are known regulators of sexual differentiation of peripheral tissues, our current data indicate that individual heterozygous mutations in Gli2+/- or Gli3+/𝛥;699 may not be sufficient to disrupt peripheral tissue development, but have important consequences on juvenile anxiety-like behavior. These observations serve as a reminder that many of the same developmental pathways are used in organogenesis and brain development.
Back to 2022 Abstracts