Laboratory of Odontogenesis and Osteogenesis, Institute of Animal Physiology and Genetics, Academy of Sciences , Brno , Czech Republic.
Department of Developmental Biology, Institute of Experimental Medicine, Czech Academy of Sciences , Prague , Czech Republic.
Organogenesis. 2019;15(4):111-119. doi: 10.1080/15476278.2019.1656995. Epub 2019 Sep 4.
Sprouty proteins are modulators of the MAPK/ERK pathway. Amongst these, Sprouty2 (SPRY2) has been investigated as a possible factor that takes part in the initial phases of osteogenesis. However, the context has not yet been investigated and the underlying mechanisms taking place remain unknown. Therefore, in this study, the impact of deficiency was examined in the developing tibias of deficient () mouse. The investigation was performed when the osteogenic zone became clearly visible and when all three basic bone cells types were present. The main markers of osteoblasts, osteocytes and osteoclasts were evaluated by immunohistochemistry and RT-PCR. RT-PCR showed that the expression of was 3.5 times higher in than in the wild-type bone, which pointed to a still unknown mechanism of action of SPRY2 on the differentiation of osteocytes. The up-regulation of was independent of expression and could not be related to its positive regulator, , since none of these factors showed an increased expression in the bone of mice. Regarding the RANK/RANKL/OPG pathway, the showed an increased expression of , but no significant change in the expression of and . Thanks to these results, the impact of deletion is shown for the first time in the developing bone as a complex organ including, particularly, an effect on osteoblasts () and osteocytes (). This might explain the previously reported decrease in bone formation in postnatal mice.
Sprouty 蛋白是 MAPK/ERK 通路的调节剂。其中,Sprouty2(SPRY2)已被研究为参与成骨初始阶段的可能因素。然而,其背景尚未得到研究,潜在的机制仍不清楚。因此,在这项研究中,研究了 缺失对 缺失()小鼠发育中胫骨的影响。当成骨区变得清晰可见且存在三种基本的骨细胞类型时,进行了该研究。通过免疫组织化学和 RT-PCR 评估了成骨细胞、骨细胞和破骨细胞的主要标志物。RT-PCR 显示,与野生型骨相比,中的 表达高出 3.5 倍,这表明 SPRY2 对骨细胞分化的作用机制仍不清楚。的上调独立于 的表达,并且不能与它的正调节剂 相关,因为在 小鼠的骨中,这些因子都没有表达增加。关于 RANK/RANKL/OPG 通路,显示 表达增加,但 和 的表达没有显著变化。由于这些结果,首次在发育中的骨骼作为一个复杂的器官中显示了 缺失的影响,特别是对成骨细胞()和骨细胞()的影响。这可能解释了先前报道的出生后 小鼠骨形成减少的现象。