Alpha1-chimaerin is a GTPase-activating protein (GAP) for Rac1, a member of the Rho small GTPase family, whose action leads to the inactivation of Rac1. is the first to demonstrate the localization of neurotoxicity in the brain of AD patients [27,28]. Thus, it will be of great interest to clarify the interaction between 1-chimaerin and Cdk5. 5. Conclusion In this study, we investigated the expression and localization of 1-chimaerin mRNA in postmortem brains from patients with AD and control subjects. In situ hybridization studies demonstrated that 1-chimaerin was expressed by neurons in the temporal lobe and the hippocampus, and staining intensity was reduced in AD cases. Real-time PCR analysis confirmed a significant reduction of 1-chimaerin mRNA expression in the brain of AD cases compared to controls, while there was no significant difference in 2-chimaerin mRNA levels between the groups. ? Highlights Alpha1-chimaerin mRNA was localized to neurons in postmortem human brain. Reduced mRNA levels of 1-chiamerin in the temporal cortex and hippocampus of AD. Expression of 2-chimaerin mRNA was not reduced in the AT-101 supplier temporal cortex of AD. Supplementary Material 1Click here to view.(1.1M, docx) Acknowledgments This study was supported in part by a Grant-in-Aid for Scientific Research on Innovative Areas (Brain Environment) (26111709) and (B) (2629002) from the Ministry of Education, Ctgf Science, Sports and Culture of Japan. We are grateful to the Banner Sun Health Research Institute Brain and Body Donation Program of Sun City, Arizona for the provision AT-101 supplier of human brain tissue. The Brain and Body Donation Program is supported by the National Institute of Neurological Disorders and Stroke (U24 NS072026 National Brain and Tissue Resource for Parkinson’s Disease and Related Disorders), the National Institute on Aging (P30 AG19610 Arizona Alzheimer’s Disease Core Center), the Arizona Department of Health Services (contract 211002, Arizona Alzheimer’s Research Center), the Arizona Biomedical Research Commission (contracts 4001, 0011, 05-901 and 1001 AT-101 supplier to the Arizona Parkinson’s Disease Consortium) and the Michael J. Fox Foundation for Parkinson’s Research. Footnotes Disclosure statement for authors: Dr. Thomas G. Beach is a paid consultant with GE Healthcare and Avid Radiopharmaceuticals. The ethics committee at Shiga University of Medical Science verified that appropriate approval and procedures were used in this study including human subjects (#13C55). Appendix A. Supplementary data: Supplementary data associated with this article can befound, in the online version, at http://dx.doi.org/10.1016/j.neulet.2015.02.013..