BMAL1 is a core component of the circadian clock loop, which directs the sophisticated circadian expression of clock-controlled genes. Skeletal Bone development is a complex biological process involving intramembranous ossification, endochondral ossification and bone remodeling, as well as specific cells, such as mesenchymal cells, osteoblasts, osteoclasts, chondrocytes, etc. Growing evidences suggest that BMAL1 is indispensable for hard tissue development, including bone, cartilage and teeth. Loss of BMAL1 in animals can inhibit bone and cartilage development, and result in abnormal bone mass. In mesenchymal cells, BMAL1 defect inhibits osteoblastic and chondrocytic differentiation. Inactivation of BMAL1 also can promote the differentiation and formation of osteoclasts and increase bone resorption. Specifically, preclinical data demonstrate that the abnormity of BMAL1 expression is associated with skeletal disorders such as skeletal mandibular hypoplasia, osteoarthritis, osteoporosis, etc. In this review, we systemically describe the impact of BMAL1 in skeletal development and homeostasis, and devote to searching new therapy strategies for bone disorders.

中文翻译：

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BMAL1在骨骼发育和疾病中的生物学功能。

BMAL1是昼夜节律循环的核心组件，它指导着时钟控制基因的复杂昼夜节律表达。骨骼骨发育是一个复杂的生物过程，涉及膜内骨化，软骨内骨化和骨重塑，以及特定的细胞，例如间充质细胞，成骨细胞，破骨细胞，软骨细胞等。越来越多的证据表明，BMAL1对于硬组织发育是必不可少的。骨骼，软骨和牙齿。动物中BMAL1的丢失会抑制骨骼和软骨的发育，并导致异常的骨量。在间充质细胞中，BMAL1缺陷抑制成骨细胞和软骨细胞的分化。BMAL1的失活还可以促进破骨细胞的分化和形成并增加骨吸收。特别，