Open AccessDecreased locomotor activity in mice expressing tTA under control of the CaMKIIα promoter
Author(s) -
McKinney B. C.,
Schneider J. S.,
Schafer G. L.,
Lowing J. L.,
Mohan S.,
Zhao M. X.,
Heng M. Y.,
Albin R. L.,
Seasholtz A. F.,
Akil H.,
Murphy G. G.
Publication year - 2008
Publication title -
genes, brain and behavior
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.315
H-Index - 91
eISSN - 1601-183X
pISSN - 1601-1848
DOI - 10.1111/j.1601-183x.2007.00339.x
Subject(s) - transgene , genetically modified mouse , rotarod performance test , forebrain , phenotype , wild type , endocrinology , transactivation , medicine , biology , locomotor activity , chemistry , mutant , neuroscience , motor activity , genetics , gene , gene expression , central nervous system
Transgenic mice in which the tetracycline transactivator (tTA) is driven by the forebrain‐specific calcium–calmodulin‐dependent kinase IIα promoter (CaMKIIα‐tTA mice) are used to study the molecular genetics of many behaviors. These mice can be crossed with other transgenic mice carrying a transgene of interest coupled to the tetracycline‐responsive promoter element to produce mice with forebrain‐specific expression of the transgene under investigation. The value of using CaMKIIα‐tTA mice to study behavior, however, is dependent on the CaMKIIα‐tTA mice themselves lacking a behavioral phenotype with respect to the behaviors being studied. Here we present data that suggest CaMKIIα‐tTA mice have a behavioral phenotype distinct from that of their wild‐type (WT) littermates. Most strikingly, we find that CaMKIIα‐tTA mice, both those with a C57BL/6NTac genetic background (B6‐tTA) and those with a 129S6B6F1/Tac hybrid genetic background (F1‐tTA), exhibit decreased locomotor activity compared with WT littermates that could be misinterpreted as altered anxiety‐like behavior. Despite this impairment, neither B6‐tTA nor F1‐tTA mice perform differently than their WT littermates in two commonly used learning and memory paradigms – Pavlovian fear conditioning and Morris water maze. Additionally, we find data regarding motor coordination and balance to be mixed: B6‐tTA mice, but not F1‐tTA mice, exhibit impaired performance on the accelerating rotarod and both perform as well as their WT littermates on the balance beam.