Absence of SHATI/Nat8l reduces social interaction in mice
NEUROSCIENCE LETTERS
Authors: Furukawa-Hibi, Yoko; Nitta, Atsumi; Fukumitsu, Hidefumi; Somiya, Hitomi; Toriumi, Kazuya; Furukawa, Shoei; Nabeshima, Toshitaka; Yamada, Kiyofumi
Abstract
We previously identified a novel molecule "Shati/Nat8l" from the nucleus accumbens of mice. However, the physiological roles of the SHATI protein are not clear. To investigate the effect of SHATI on the central nervous system and behavior, we studied knockout mice of this protein. We carried out various behavior tests using Shari-knockout mice. Shati-knockout mice did not differ from wild type mice in learning and memory. In the open field test, Shari-knockout mice did not differ from wild-type mice in time of stay in the outer, middle and center areas. On the other hand, Shari-knockout mice showed increases in rearing and grooming time in the open field test, and exploration time of novel objects. These results suggested that knockout of the Shari gene may increase exploration in specific circumstances. Interestingly, the Shati-knockout mice avoided social interaction with unfamiliar mice out of their home cage, although there was no difference in social interaction in their home cage compared with wild type mice. Lack of the Shari gene increased brain-derived neurotrophic factor (BDNF) mRNA in the prefrontal cortex and hippocampus, and decreased glial cell line-derived neurotrophic factor (GDNF) mRNA in the striatum and hippocampus, and lipopolysaccharides-induced TNF-alpha factor (LITAF) mRNA in the striatum. Since these factors play important roles in behavior, alteration of expression of these factors may be related to the induction of exploration and reduction of social interaction in Shari-knockout mice. (C) 2012 Elsevier Ireland Ltd. All rights reserved.
Shati/Nat8l deficiency disrupts adult neurogenesis and causes attentional impairment through dopaminergic neuronal dysfunction in the dentate gyrus
JOURNAL OF NEUROCHEMISTRY
Authors: Wulaer, Bolati; Kunisawa, Kazuo; Hada, Kazuhiro; Suento, Willy Jaya; Kubota, Hisayoshi; Iida, Tsubasa; Kosuge, Aika; Nagai, Taku; Yamada, Kiyofumi; Nitta, Atsumi; Yamamoto, Yasuko; Saito, Kuniaki; Mouri, Akihiro; Nabeshima, Toshitaka
Abstract
Successful completion of daily activities relies on the ability to select the relevant features of the environment for memory and recall. Disruption to these processes can lead to various disorders, such as attention-deficit hyperactivity disorder (ADHD). Dopamine is a neurotransmitter implicated in the regulation of several processes, including attention. In addition to the higher-order brain function, dopamine is implicated in the regulation of adult neurogenesis. Previously, we generated mice lacking Shati, an N-acetyltransferase-8-like protein on a C57BL/6J genetic background (Shati/Nat8l(-/-)). These mice showed a series of changes in the dopamine system and ADHD-like behavioral phenotypes. Therefore, we hypothesized that deficiency of Shati/Nat8l would affect neurogenesis and attentional behavior in mice. We found aberrant morphology of neurons and impaired neurogenesis in the dentate gyrus of Shati/Nat8l(-/-) mice. Additionally, research has suggested that impaired neurogenesis might be because of the reduction of dopamine in the hippocampus. Galantamine (GAL) attenuated the attentional impairment observed in the object-based attention test via increasing the dopamine release in the hippocampus of Shati/Nat8l(-/-) mice. The alpha 7 nicotinic acetylcholine receptor antagonist, methyllycaconitine, and dopamine D1 receptor antagonist, SCH23390, blocked the ameliorating effect of GAL on attentional impairment in Shati/Nat8l(-/-) mice. These results suggest that the ameliorating effect of GAL on Shati/Nat8l(-/-) attentional impairment is associated with activation of D1 receptors following increased dopamine release in the hippocampus via alpha 7 nicotinic acetylcholine receptor. In summary, Shati/Nat8l is important in both morphogenesis and neurogenesis in the dentate gyrus and attention, possible via modulation of dopaminergic transmission.