NINDS GENSAT BAC Transgenics Project

The Rockefeller University

The Gensat database contains a gene expression atlas of the central nervous system of the mouse based on bacterial artificial chromosomes (BACs). In each of the BAC transgenic vectors, endogenous protein coding sequences have been replaced by sequences encoding the EGFP reporter gene. As in any gene replacement experiment, the stability of the reporter gene can vary somewhat from the endogenous gene. Thus these results measure the relative rates of transcription for each gene; they are not a direct measure of mRNA accumulation or of protein abundance for the endogenous gene products. Furthermore, the enhanced sensitivity of reporter gene assays, particularly in BAC lines carrying multiple copies of the BAC transgene may allow detection of sites of expression that are not evident in situ hybridization experiments. This database contains histological data from given BAC transgenic mouse lines at three developmental stages – embryonic day 15.5 (E15.5), postnatal day 7 (P7) and adult; in all cases the data represent results of multiple transgenic lines. EGFP is visualized by staining with an anti-EGFP antibody using the DAB method, or by confocal microscopy of unstained tissue sections. Protocols for the modification of BACs, BAC transgenesis production and histology are provided.

This resource may be useful for the following types of experiments:

  • Gene Expression: reporter genes – precise information can lead to precise hypothesis regarding function
  • Protein localization/purification: epitope tags, fusion proteins – direct analysis of complex protein assemblies in the intact brain
  • Neuronal Connectivity: tract tracer – connectivity of CNS circuits
  • Transcriptional Profiling: affinity purification of polysomes – cell specific array analysis
  • In vivo cell labeling: electrophysiology, imaging of neuronal activity and synaptic change
  • Genetic Analysis: Correlating altered behavior with changes in the nervous system.

Reference: Gong S, Zheng C, Doughty ML, Losos K, Didkovsky N, Schambra UB, Nowak NJ, Joyner A, Leblanc G, Hatten ME, Heintz N. “A gene expression atlas of the central nervous system based on bacterial artificial chromosomes.” Nature, October 30, 2003, Vol. 425, pp. 917-925.