CCR5 closes the temporal window for memory linking. 

Shen Y, Zhou M, Cai D, Filho DA, Fernandes G, Cai Y, de Sousa AF, Tian M, Kim N, Lee J, Necula D, Zhou C, Li S, Salinas S, Liu A, Kang X, Kamata M, Lavi A, Huang S, Silva T, Heo WD, Silva AJ.