Abnormalities in GABAergic inhibitory circuits have been implicated in the aetiology of autism spectrum disorder (ASD). ASD is caused by genetic and environmental factors. Several genes have been associated with syndromic forms of ASD, including FOXG1. However, when and how dysregulation of FOXG1 can result in defects in inhibitory circuit development and ASD-like social impairments is unclear. Here, we show that increased or decreased FoxG1 expression in both excitatory and inhibitory neurons results in ASD-related circuit and social behavior deficits in our mouse models. We observe that the second postnatal week is the critical period when regulation of FoxG1 expression is required to prevent subsequent ASD-like social impairments. Transplantation of GABAergic precursor cells prior to this critical period and reduction in GABAergic tone via Gad2 mutation ameliorates and exacerbates circuit functionality and social behavioral defects, respectively. Our results provide mechanistic insight into the developmental timing of inhibitory circuit formation underlying ASD-like phenotypes in mouse models.

Individual cell shape and integrity must precisely be orchestrated during morphogenesis. Here, we determine function of type II cadherins, Cdh6, Cdh8, and Cdh11, whose expression combinatorially demarcates the mouse neural plate/tube. While CRISPR/Cas9-based single type II cadherin mutants show no obvious phenotype, Cdh6/8 double knockout (DKO) mice develop intermingled forebrain/midbrain compartments as these two cadherins’ expression opposes at the nascent boundary. Cdh6/8/11 triple, Cdh6/8 or Cdh8/11 DKO mice further cause exencephaly just within the cranial region where mutated cadherins’ expression merges. In the Cdh8/11 DKO midbrain, we observe less-constricted apical actin meshwork, ventrally-directed spreading, and occasional hyperproliferation among dorsal neuroepithelial cells as origins for exencephaly. These results provide rigid evidence that, by conferring distinct adhesive codes to each cell, redundant type II cadherins serve essential and shared roles in compartmentalization and neurulation, both of which proceed under the robust control of the number, positioning, constriction, and fluidity of neuroepithelial cells.

We analysed the effect of three antioxidants that have different functional mechanisms on the in vitro maturation (IVM) of porcine oocytes. Single oocyte monoculture using the hanging drop (HD) system has some advantages such as improving analysis efficiency brought by the smaller number of samples than the number of oocytes cultured in one drop. Direct effects of ligands on single oocytes could also be detected without considering the effects of paracrine factors from other oocytes. After 22 h of pre-culture, denuded oocytes were cultured for 22 h with 0.01 and 0.1 μg/ml of L-carnitine (LC), lactoferrin (LF) or sulforaphane (SF) in the presence/non-presence of oxidant stress induced by H2O2 supplementation to evaluate the reducing effects against oxidative stress on nuclear maturation. As a result, compared with LC and SF, LF showed effective reduction in oxidative stress at a lower concentration (0.01 μg/ml), suggesting that LF is a more effective antioxidant in porcine oocyte IVM. Additionally, LF also increased maturation rate even in culture without H2O2. Our results clearly suggest that the HD monoculture system is useful for screening the substances that affect porcine oocyte culture.

Localization patterns of lipid droplets in the cytoplasm of porcine oocytes were evaluated as a novel marker for in vitro maturation (IVM) of oocytes with high developmental competence. Porcine oocytes were cultured in TCM-199, which is a complete synthetic medium, for 44 h at 38.5 C. Localization patterns were divided into 2 classes: lipid droplets localized uniformly in the whole cytoplasm (class I) and those that were centrally located (class II). After IVM in TCM-199, 60% of matured oocytes exhibited the class II pattern. To investigate the relation between the distribution of lipid droplets and the developmental rate of the oocyte, the developmental rates of class I and class II oocytes were compared after in vitro fertilization (IVF). Class II oocytes showed a significantly higher rate of blastocyst development than class I oocytes. These results suggest that porcine oocytes with high developmental competence can be selected based on the localization patterns of lipid droplets.

Acetamiprid (ACE) and imidacroprid (IMI) are known neonicotinoid insecticides with strong affinities for the insect-selective nicotinic acetylcholine receptor. These provide insect control by hyperstimulating insect nerves and are used for agricultural pest management. However, it has also been reported that ACE and IMI affect mammalian reproductive function. We determined the effects of ACE and IMI on the in vitro maturation of porcine oocytes. Significant decreases in nuclear maturation rates were observed in the ACE or IMI-exposed groups. Also, in matured oocytes from the ACE or IMI-exposed groups, irregular chromosomes were observed. Our results suggest that ACE and IMI exposure was detrimental to porcine oocytes and the extent of the effects depends on the concentration of exposure.