Adeno-associated virus effectively mediates conditional gene modification in the brain

Abstract

The Cre͞loxP system is increasingly showing promise for investigating genes involved in neural function. Here, we demonstrate that in vivo modification of genes in the mouse brain can be accomplished in a spatial-and temporal-specific manner by targeted delivery of an adeno-associated virus (AAV) encoding a green fluorescent protein͞Cre recombinase (GFP͞Cre) fusion protein. By using a reporter mouse, in which Cre recombinase activates ␤-galactosidase expression, we demonstrate long-term recombination of neurons in the hippocampus, striatum, and septum as early as 7 days after stereotaxic injection of virus. Recombined cells were observed for at least 6 months postinjection without evidence of cell loss or neural damage. AAV-mediated delivery of GFP͞Cre provides a valuable approach to alter the mouse genome, as AAV delivers genes efficiently to neurons with low toxicity. This approach will greatly facilitate the study of genetic modifications in the mouse brain.gene transfer ͉ Cre recombinase ͉ transgenic mouse ͉ loxP ͉ ROSA26

Conditional deletion of the NMDA-NR1 receptor subunit gene in the central nucleus of the amygdala inhibits naloxone-induced conditioned place aversion in morphine-dependent mice

“…However, unlike other adenovirus vectors, the rAAV has not been shown to produce pathogenic or immune reactions, as indicated by the lack of vascular cuffing, as well as the absence of glial-, CD4-, or CD8-cell infiltration in the target site following intracranial microinjection (Kaspar et al, 2002). Moreover, it has also been shown that rAAV injection in the spinal cord of fNR1 mice does not produce neuronal loss, as measured by NeuN labeling (South et al, 2003).…”

“…An alternative approach involves intracerebral microinjection of a recombinant adenoassociated virus (rAAV) expressing a fusion protein of Cre and a reporter, green fluorescent protein (GFP), termed "rAAV-GFP-Cre" (Kaspar et al, 2002;South et al 2003). A vector not expressing Cre (rAAV-GFP) is used as a control.…”

Hippocampal Focal Knockout of CBP Affects Specific Histone Modifications, Long-Term Potentiation, and Long-Term Memory

“…Cre recombinase can be introduced to delete the sequence between the loxP sites, producing deletion of CBP (Kang-Decker et al, 2004;Kasper et al, 2006;Xu et al, 2006). At 2 weeks before the experiments, mice were anesthetized using isoflurane and infused with adeno-associated virus expressing Cre-recombinase (AAV-Cre), either serotype AAV2/2 (made in the lab of RWG), or AAV2/1 (purchased from Penn Vector Core; University of Pennsylvania; Kaspar et al, 2002). The infusion cannula was positioned over the hippocampus (AP À2.0 mm; ML ± 1.5 mm from bregma) and lowered 0.2 mm/15 s to a depth of À1.5 mm (DV from bregma).…”

Targeted axonal import (TAxI) peptide delivers functional proteins into spinal cord motor neurons after peripheral administration

“…Whereas Cre has been delivered in vivo by viral gene delivery using adenovirus, lentivirus, and adeno-associated virus (36)(37)(38), the data we describe herein is the first nonviral delivery paradigm to our knowledge to deliver a biologically active Cre in vivo. Whereas viral delivery can provide high levels of stable expression, TAxI-mediated delivery of proteins offers better control over dosing and would be better tolerated in repeat dosing regimens.…”