Mouse Cre Models for the Study of Bone Diseases
Transgenic Cre lines are a valuable tool for conditionally inactivating or activating genes to understand their function. Here, we provide an overview of Cre transgenic models used for studying gene function in bone cells and discuss their advantages and limitations, with particular emphasis on Cre lines used for studying osteocyte and osteoclast function.
Recent studies have shown that many bone cell-targeted Cre models are not as specific as originally thought. To ensure accurate data interpretation, it is important for investigators to test for unexpected recombination events due to transient expression of Cre recombinase during development or in precursor cells and to be aware of the potential for germ line recombination of targeted genes as well as the potential for unexpected phenotypes due to the Cre transgene.
Although many of the bone-targeted Cre-deleter strains are imperfect and each model has its own limitations, their careful use will continue to provide key advances in our understanding of bone cell function in health and disease.
KeywordsOsteocyte Osteoclast Cre recombinase Conditional knockout Cre-loxP Bone
SLD was supported by NIH grants P01-AG039355 and R21-AR071563. YU was supported by NIH grants R01-DE025870 and R21-AR070953. YX and LAS were supported by NIH grant P01-AG039355, which also supported the data in Fig. 2.
Compliance with Ethical Standards
Conflict of Interest
Lora Shiflett, Sarah Dallas, Yixia Xie and Yasuyoshi Ueki declare no conflict of interest.
Human and Animal Rights and Informed Consent
All reported studies/experiments with animal subjects performed by the authors have complied with all applicable ethical standards (including the Helsinki declaration and its amendments, institutional/national research committee standards, and international/national/institutional guidelines).
Papers of particular interest, published recently, have been highlighted as: •• Of major Importance
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