Canonical Wnt signaling activates miR-34 expression during osteoblastic differentiation
Canonical Wnt signaling activates miR-34 expression during osteoblastic differentiation
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DOI：
10.3892/mmr.2013.1713
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发表时间：
2013-12-01
影响因子：
3.4
通讯作者：
Sato, Mari
中科院分区：
文献类型：
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作者：
Tamura, Masato;Uyama, Maki;Sato, Mari
经典Wnt信号通路对于人类骨量的调节和成骨细胞的发育至关重要。MicroRNA（miRs）代表一类长度类似于22个核苷酸的非编码RNA，其通过靶向mRNA进行切割或翻译抑制来调节基因表达。一些先前的研究已经证明了miRNA参与调节成骨细胞中的基因表达和调节成骨细胞分化。在本研究中，使用Wnt 3a-C2 C12细胞进行microRNA分析;用Wnt 3a表达质粒转染C2 C12细胞以激活经典Wnt信号传导。在C2 C12细胞中，miR-34 b-5 p和miR-34 c被鉴定为通过典型Wnt信号传导的激活而上调。成熟miR-34 b/c的表达从MC 3 T3-E1细胞分化的第0天的低水平增加到第28天的最大水平。为了分析这些miRNAs对成骨细胞分化的影响，将反义抑制剂转染到MC 3 T3-E1细胞中，并研究成骨细胞相关基因的表达。miR 34 b/c的敲低增强了骨钙素mRNA的表达;然而，miR 34 b/c的抑制降低了碱性磷酸酶mRNA的表达和活性。这些结果表明，miR-34 b/c通过靶向成骨途径的调节因子来调节基因表达，从而有助于成骨细胞分化。
The canonical Wnt signaling pathway is crucial for the regulation of bone mass in humans and for the development of osteoblasts. MicroRNAs (miRs) represent a class of non-coding RNAs, similar to 22 nucleotides in length, that regulate gene expression by targeting mRNAs for cleavage or translational repression. Several previous studies have demonstrated the involvement of miRNAs in modulating gene expression in osteoblasts and regulating osteoblast differentiation. In the present study, microRNA profiling was conducted using Wnt3a-C2C12 cells; C2C12 cells were transfected with a Wnt3a expression plasmid to activate canonical Wnt signaling. miR-34b-5p and miR-34c were identified to be upregulated by the activation of canonical Wnt signaling in C2C12 cells. Expression of mature miR-34b/c increased from low levels at day 0 to maximum levels at day 28 of MC3T3-E1 cell differentiation. To analyze the effects of these miRNAs on osteoblast differentiation, an antisense inhibitor was transfected into MC3T3-E1 cells and osteoblast-related gene expression was investigated. Knockdown of miR34b/c enhanced osteocalcin mRNA expression; however, alkaline phosphatase mRNA expression and activity were decreased by miR34b/c inhibition. These results indicated that miR-34b/c regulates gene expression by targeting regulators of the osteogenic pathways and thereby contributes to osteoblast differentiation.