Project description:We previously found that mice with heterozygous knockout of the alpha-isoform of calcium/calmodulin-dependent protein kinase II (alpha-CaMKII HKO mice) show various dysregulated behaviors, including cyclic variations in locomotor activity (LA), suggesting that alpha-CaMKII HKO mice may serve as an animal model showing infradian oscillation of mood. We performed gene expression microarray analysis of dentate gyrus from alpha-CaMKII HKO mice. Mice were selected for the sampling such that their LA levels varied among the mice. Dentate gyrus RNA isolated from alpha-CaMKII HKO mice.
Project description:We previously found that mice with heterozygous knockout of the alpha-isoform of calcium/calmodulin-dependent protein kinase II (alpha-CaMKII HKO mice) show various dysregulated behaviors, including cyclic variations in locomotor activity (LA), suggesting that alpha-CaMKII HKO mice may serve as an animal model showing infradian oscillation of mood. We performed gene expression microarray analysis of dentate gyrus from alpha-CaMKII HKO mice. Mice were selected for the sampling such that their LA levels varied among the mice.
Project description:Engrams are considered to be substrates for memory storage, and the functional dysregulation of the engrams leads to cognition impairment.However, the cellular basis for these maladaptive changes lead to the forgetting of memories remains unclear. Here we found that the expression of autophagy protein 7 (Atg7) mRNA was dramatically upregulated in aged DG engrams, and led to the forgetting of contextual fear memory and the activation of surrounding microglia.To determine mechanism by which autophagy in DG engrams activates the surrounding microglia, mice were co-injected AAV-RAM-Cre either with AAV-Dio-Atg7-Flag or AAV-Dio- EYFP in dorsal dentate gyrus to overexpress ATG7 in the DG memory engrams. Microglia were separated using magnetic-activated cell sorting and subjected to RNA-Seq in dorsal hippocampus .Bioinformatics analysis shown overexpression of Atg7 in dorsal DG memory engrams caused an increase in the expression of Tlr2 in the surrounding microglia.Depletion of Toll-like receptor 2/4 (TLR2/4) in DG microglia prohibited excessive microglial activation and synapse elimination induced by the overexpression of ATG7 in DG engrams, and thus prevented forgetting. Furthermore, the expression of Rac1, a Rho-GTPases which regulates active forgetting in both fly and mice, was upregulated in aged engrams. Optogentic activation of Rac1 in DG engrams promoted the autophagy of the engrams, the activation of microglia, and the forgetting of fear memory. Invention of the Atg7 expression and microglia activation attenuated forgetting induced by activation of Rac1 in DG engrams. Together, our findings revealed autophagy-dependent synapse elimination of DG engrams by microglia as a novel forgetting mechanism.
Project description:To search gene expression change of dentate gyrus in the central nervous system-specific Derlin-1or Derlin-2 mice, we performed genome-wide DNA microarray analysis and compared the expression levels between Derlin-1 or 2 _control and Derlin-1 or 2_KO.