Cre/loxP technology has been widely used to study cell type-specific functions of genes. Proper interpretation of such data critically depends on a clear understanding of the tissue specificity of Cre expression. The ...Cre/loxP technology has been widely used to study cell type-specific functions of genes. Proper interpretation of such data critically depends on a clear understanding of the tissue specificity of Cre expression. The Dmpl- Cre mouse, expressing Cre from a 14-kb DNA fragment of the mouse Dmpl gene, has become a common tool for studying gene function in osteocytes, but the presumed cell specificity is yet to be fully established. By using the Ai9 reporter line that expresses a red fluorescent protein upon Cre recombination, we find that in 2-month-old mice, Dmpl-Cre targets not only osteocytes within the bone matrix but also osteoblasts on the bone surface and preosteoblasts at the metaphyseal chondro-osseous junction. In the bone marrow, Cre activity is evident in certain stromal cells adjacent to the blood vessels, but not in adipocytes. Outside the skeleton, Dmpl-Cre marks not only the skeletal muscle fibers, certain cells in the cerebellum and the hindbrain but also gastric and intestinal mesenchymal cells that express Pdgfra. Confirming the utility of Dmpl-Cre in the gastrointestinal mesenchyme, deletion of Bmprla with Dmpl-Cre causes numerous large polyps along the gastrointestinal tract, consistent with prior work involving inhibition of BMP signaling. Thus, caution needs to be exercised when using Dmpl-Cre because it targets not only the osteoblast lineage at an earlier stage than previously appreciated, but also a number of non-skeletal cell types.展开更多
目的:观察牙本质基质蛋白1(dentin matrix protein 1,DMP1)在舌鳞癌细胞Cal-27、Tca-8113以及人永生化表皮细胞Hacat中的表达情况,初步探讨DMP1与口腔鳞癌的相关性。方法:免疫荧光染色用于人永生化表皮细胞Hacat与舌鳞癌细胞Cal-27中,...目的:观察牙本质基质蛋白1(dentin matrix protein 1,DMP1)在舌鳞癌细胞Cal-27、Tca-8113以及人永生化表皮细胞Hacat中的表达情况,初步探讨DMP1与口腔鳞癌的相关性。方法:免疫荧光染色用于人永生化表皮细胞Hacat与舌鳞癌细胞Cal-27中,于共聚焦显微镜下观察DMP1在两组细胞的染色情况;采用Western blot方法,分别提取Hacat,Cal-27和人舌鳞癌细胞Tca-8113中DMP1蛋白并检测其含量。结果:通过免疫荧光实验观察到DMP1在Cal-27细胞及Hacat细胞中都表达于细胞质,同时发现DMP1在Hacat细胞中的荧光强度为41.2,高于Cal-27细胞荧光强度26.5;Western blot实验结果显示Hacat细胞中DMP1蛋白的灰度分析值为100和109,明显高于Cal-27和Tca-8113细胞的40.8和37.6。结论:DMP1在口腔鳞癌细胞和Hacat细胞中的表达存在差异,提示DMP1可能与口腔鳞癌的发生相关。展开更多
基金supported by NIH grants AR060456 and AR055923(FL)supported by NIH DK105129,DK094989,by DK052574 to the Washington University Digestive Core Centers(DDRCC)+6 种基金by the pre-Program Project Award from the Siteman Cancer Center Investment Programsupported by the NIGMS cell and Molecular Biology Training Grant(GM007067)supported by the NIH funded George O’Brien Center for Kidney Disease Research(P30DK079333)Kidney translational Research Core and the Renal Division at the Washington University School of Medicinesupported by the Alafi Neuroimaging Laboratorythe Hope Center for Neurological DisordersNIH Shared Instrumentation Grant(S10 RR0227552)to Washington University
文摘Cre/loxP technology has been widely used to study cell type-specific functions of genes. Proper interpretation of such data critically depends on a clear understanding of the tissue specificity of Cre expression. The Dmpl- Cre mouse, expressing Cre from a 14-kb DNA fragment of the mouse Dmpl gene, has become a common tool for studying gene function in osteocytes, but the presumed cell specificity is yet to be fully established. By using the Ai9 reporter line that expresses a red fluorescent protein upon Cre recombination, we find that in 2-month-old mice, Dmpl-Cre targets not only osteocytes within the bone matrix but also osteoblasts on the bone surface and preosteoblasts at the metaphyseal chondro-osseous junction. In the bone marrow, Cre activity is evident in certain stromal cells adjacent to the blood vessels, but not in adipocytes. Outside the skeleton, Dmpl-Cre marks not only the skeletal muscle fibers, certain cells in the cerebellum and the hindbrain but also gastric and intestinal mesenchymal cells that express Pdgfra. Confirming the utility of Dmpl-Cre in the gastrointestinal mesenchyme, deletion of Bmprla with Dmpl-Cre causes numerous large polyps along the gastrointestinal tract, consistent with prior work involving inhibition of BMP signaling. Thus, caution needs to be exercised when using Dmpl-Cre because it targets not only the osteoblast lineage at an earlier stage than previously appreciated, but also a number of non-skeletal cell types.
