DEVELOPMENTAL NEUROSCIENCEExperience-dependent expression of terminal deoxynucleotidyl transferase in mouse brainPeña de Ortiz, SandraCA; Colón, Melissa; Carrasquillo, Yarimar1; Padilla, Beatriz; Arshavsky, Yuri I.2 Author Information Department of Biology, University of Puerto Rico, Río Piedras Campus, Gándara Avenue, Julio García Díaz Building Room 202, P.O. Box 23360, San Juan, PR 00931-3360 2Institute for Nonlinear Science, University of California at San Diego, CA 92093-0402, USA 1Present Address: Department of Molecular Neuroscience, Baylor School of Medicine, USA Received 16 December 2002; accepted 21 February 2003 CACorresponding Author: [email protected] NeuroReport: June 11, 2003 - Volume 14 - Issue 8 - p 1141-1144 Buy Abstract Terminal deoxynucleotidyl transferase (TdT), a template-independent DNA polymerase, contributes to antigen receptor diversity in lymphocytes. Using in situ hybridization, we found that tdt is expressed within neurons of the adult mouse brain. tdt mRNA was localized within pyramidal neurons in the hippocampus, granule and polymorphic cells in the dentate gyrus, Purkinje neurons in the cerebellum, and cortical cells. Increased levels of tdt mRNA in the hippocampus, neocortex, and cerebellum were associated with rearing C57BL/6 mice, but not DBA/2 mice, in enriched environments. Unlike wild types (WT), tdt−/− mice did not show improvement in spatial learning and memory as a result of rearing in enriched environments. These results suggest that tdt may be involved in learning and memory saving. © 2003 Lippincott Williams & Wilkins, Inc.