SCORHE: A novel and practical approach to video monitoring of laboratory mice housed in vivarium cage racks
BEHAVIOR RESEARCH METHODS
Authors: Salem, Ghadi H.; Dennis, John U.; Krynitsky, Jonathan; Garmendia-Cedillos, Marcial; Swaroop, Kanchan; Malley, James D.; Pajevic, Sinisa; Abuhatzira, Liron; Bustin, Michael; Gillet, Jean-Pierre; Gottesman, Michael M.; Mitchell, James B.; Pohida, Thomas J.
Abstract
The System for Continuous Observation of Rodents in Home-cage Environment (SCORHE) was developed to demonstrate the viability of compact and scalable designs for quantifying activity levels and behavior patterns for mice housed within a commercial ventilated cage rack. The SCORHE in-rack design provides day- and night-time monitoring with the consistency and convenience of the home-cage environment. The dual-video camera custom hardware design makes efficient use of space, does not require home-cage modification, and is animal-facility user-friendly. Given the system's low cost and suitability for use in existing vivariums without modification to the animal husbandry procedures or housing setup, SCORHE opens up the potential for the wider use of automated video monitoring in animal facilities. SCORHE's potential uses include day-to-day health monitoring, as well as advanced behavioral screening and ethology experiments, ranging from the assessment of the short- and long-term effects of experimental cancer treatments to the evaluation of mouse models. When used for phenotyping and animal model studies, SCORHE aims to eliminate the concerns often associated with many mouse-monitoring methods, such as circadian rhythm disruption, acclimation periods, lack of night-time measurements, and short monitoring periods. Custom software integrates two video streams to extract several mouse activity and behavior measures. Studies comparing the activity levels of ABCB5 knockout and HMGN1 overexpresser mice with their respective C57BL parental strains demonstrate SCORHE's efficacy in characterizing the activity profiles for singly- and doubly-housed mice. Another study was conducted to demonstrate the ability of SCORHE to detect a change in activity resulting from administering a sedative.
Differential expression of the HMGN family of chromatin proteins during ocular development
GENE EXPRESSION PATTERNS
Authors: Lucey, Michelle M.; Wang, Yan; Bustin, Michael; Duncan, Melinda K.
Abstract
The HMGN proteins are a group of non-histone nuclear proteins that associate with the core nucleosome and alter the structure of the chromatin fiber. We investigated the distribution of the three best characterized HMGN family members, HMGN1, HMGN2 and HMGN3 during mouse eye development. HMGN1 protein is evenly distributed in all ocular structures of 10.5 days post-coitum (dpc) mouse embryos however, by 13.5 dpc, relatively less HMGN1 is detected in the newly formed lens fiber cells compared to other cell types. In the adult, HMGN1 is detected throughout the retina and lens, although in the cornea, HMGN1 protein is predominately located in the epithelium. HMGN2 is also abundant in all ocular structures of mouse embryos, however, unlike HMGN1, intense immunolabeling is maintained in the lens fiber cells at 13.5 dpc. in the adult eye, HMGN2 protein is still found in all lens nuclei while in the cornea, HMGN2 protein is mostly restricted to the epithelium. In contrast, the first detection of HMGN3 in the eye is in the presumptive corneal epithelium and lens fiber cells at 13.5 dpc. In the lens, HMGN3 remained lens fiber cell preferred into adulthood. In the cornea, HMGN3 is transiently upregulated in the stroma and endothelium at birth while its expression is restricted to the corneal epithelium in adulthood. In the retina, HMGN3 upregulates around 2 weeks of age and is found at relatively high levels in the inner nuclear and ganglion cell layers of the adult retina. RT-PCR analysis determined that the predominant HMGN3 splice form found in ocular tissues is HMGN3b which lacks the chromatin unfolding domain although HMGN3a mRNA is also detected. These results demonstrate that the HMGN class of chromatin proteins has a dynamic expression pattern in the developing eye. (C) 2008 Elsevier B.V. All rights reserved.