The goal of the Transgenic Animal Core is to assist the investigators of each project with the design, production, characterization, and maintenance of genetically modified mice. To achieve this goal, the core will perform the following functions. First, the core will design and construct transgenes and develop genotyping assays and purify transgene DNA for microinjection. Second, the core will generate transgenic founders via microinjection of transgene DNA into fertilized eggs from the C57BL/6 strain of mice. Potentially transgenic offspring will be identified using genotyping assays developed by the core. Founder mice will be characterized for the ability to transmit the transgene to offspring. The number of independent chromosomal integration sites in each founder will be determined. Germline-competent mice, each with a transgene integrated at a single genomic locus, will be delivered to project leaders. The third service of thecore will be to design and facilitate production of gene-targeted mice. Specifically, the core will produce and purify the gene-targeting constructs and test embryonic stem (ES) cell screening assays. The core will then work with an off-site ES cell facility to introduce the DNA into ES cells and isolate appropriately targeted ES cell clones. Appropriately targeted clones will then be used for blastocyst injections. Chimeric mice will be sent to UAMS and the core will identify those with the ability to produce offspring harboring the targeted allele. Germline-competent mice will then be delivered to project leaders. Finally, the core will assist in the characterization, maintenance, and preservation of genetically-modified mice. Quantitative reversetranscriptase polymerase chain reaction (RT-PCR) assays will be designed to specifically detect transgene mRNA and then used to determine the tissue distribution of transgene mRNA expression. Expression patterns of each Cre-deleter strain will be verified by crossing with R26R Cre-reporter mice. Each new mouse model generated by the core, or imported for use by the program, will be cryo-preserved via sperm cryopreservation for long-term bio-security, cost-reduction, and efficient access.

Public Health Relevance

Genetically modified mice allow investigators to determine whether phenomena observed in cell lines and cell cultures also occur in vivo. Such mice are also used to test hypotheses that cannot be convincingly addressed in any in vitro system. Thus timely and efficient production of genetically modified mice is essential to the overall goal of the Program which is to improve the understanding of the pathophysiology of the bone fragility syndrome of osteoporosis and thereby rationalize and optimize its treatment.

National Institute of Health (NIH)
National Institute on Aging (NIA)
Research Program Projects (P01)
Project #
Application #
Study Section
Special Emphasis Panel (ZAG1-ZIJ-6)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Arkansas for Medical Sciences
Little Rock
United States
Zip Code
Farr, Joshua N; Almeida, Maria (2018) The Spectrum of Fundamental Basic Science Discoveries Contributing to Organismal Aging. J Bone Miner Res 33:1568-1584
Weinstein, Robert S; Hogan, Erin A; Borrelli, Michael J et al. (2017) The Pathophysiological Sequence of Glucocorticoid-Induced Osteonecrosis of the Femoral Head in Male Mice. Endocrinology 158:3817-3831
Kim, Ha-Neui; Chang, Jianhui; Shao, Lijian et al. (2017) DNA damage and senescence in osteoprogenitors expressing Osx1 may cause their decrease with age. Aging Cell 16:693-703
Ucer, Serra; Iyer, Srividhya; Kim, Ha-Neui et al. (2017) The Effects of Aging and Sex Steroid Deficiency on the Murine Skeleton Are Independent and Mechanistically Distinct. J Bone Miner Res 32:560-574
Iyer, Srividhya; Han, Li; Ambrogini, Elena et al. (2017) Deletion of FoxO1, 3, and 4 in Osteoblast Progenitors Attenuates the Loss of Cancellous Bone Mass in a Mouse Model of Type 1 Diabetes. J Bone Miner Res 32:60-69
Almeida, Maria; Laurent, Michaƫl R; Dubois, Vanessa et al. (2017) Estrogens and Androgens in Skeletal Physiology and Pathophysiology. Physiol Rev 97:135-187
Piemontese, Marilina; Almeida, Maria; Robling, Alexander G et al. (2017) Old age causes de novo intracortical bone remodeling and porosity in mice. JCI Insight 2:
Piemontese, Marilina; Xiong, Jinhu; Fujiwara, Yuko et al. (2016) Cortical bone loss caused by glucocorticoid excess requires RANKL production by osteocytes and is associated with reduced OPG expression in mice. Am J Physiol Endocrinol Metab 311:E587-93
Fujiwara, Toshifumi; Ye, Shiqiao; Castro-Gomes, Thiago et al. (2016) PLEKHM1/DEF8/RAB7 complex regulates lysosome positioning and bone homeostasis. JCI Insight 1:e86330
Fujiwara, T; Zhou, J; Ye, S et al. (2016) RNA-binding protein Musashi2 induced by RANKL is critical for osteoclast survival. Cell Death Dis 7:e2300

Showing the most recent 10 out of 162 publications