Generation And Phenotypical Analysis Of Osteoblastic Fbxw7 Gene Konckout Mice

Osteoblasts are important components in bone tissue,which differentiate into bone matrix during bone development and are responsible for the synthesis,secretion and mineralization of bone matrix.It secretes specific osteocalcin,alkaline phosphatase and type I collagen into the extracellular matrix,forming the most important part of the bone with support function.Defects on osteoblasts can lead to the development of bone diseases.By targeting osteoblasts,bone formation can be promoted,and it can accelerate the repair of bone structure and functional diseases.Therefore,osteoblasts play an important role in bone tissue.Fbxw7 is a key factor for substrate-specific recognition in the SCF(Skp-Cullin-F-box)ubiquitin ligase E3 complex,which controls the degradation of most proteins in cells.Studies have shown that Fbxw7 can affect the vascular and bone tissue by targeting Fbxw7 and P4HTM through the endothelial cell Notch MiR-497-195 cluster,which affects Notch in CD31hi Emcnhi bone endothelial cells,suggesting that Fbxw7 is associated with and bone tissue.Ubiquitination factors are commonly reported for use in tumor research.Ubiquitination also plays an important role in skeletal development and bone metabolism balance.The dysfunction of ubiquitin ligase is closely related to the development of bone diseases.Research results have shown that Smurfl,a HECT-type ubiquitin ligase,is an important negative regulator of bone formation,and its high expression causes bone loss.This suggests that ubiquitination factors are associated with bone metabolism.Bone metabolism processes include bone resorption and bone formation.Osteoblasts that synthesize bone matrix are indispensable components of bone tissue and play an important role in bone metabolism.Fbxw7 is an important factor in ubiquitination,and some ubiquitination factors affect bone metabolism.However,there is no definitive study to show whether the Fbxw7 gene is involved in bone metabolism,and no studies have reported the role of the Fbxw7 gene in bone metabolism in osteoblasts.Therefore,this study aimed to establish a transgenic mouse model of osteoblast cell(Bglap)knockdown of Fbxw7 gene by Cre-Loxp system to prove:whether Fbxw7 gene is involved in bone metabolism,and If involved in bone metabolism,we will explore how the Fbxw7 gene plays a role in osteoblasts.To explore the effects of Fbxw7 on osteoblasts,osteoclasts and related substances in cells and animals,and provide a new basis for the prevention and treatment of bone diseases.In this study,Cre-Loxp system was used to construct transgenic mice in which osteoblasts(bglap)were knocked out of Fbxw7 gene.The knockout effect of transgenic mice was verified by PCR,western blot and immunohistochemistry.Then,HE staining and Mirco-CT were used to analyze the effects of Fbxw7 gene on the morphology and structure of bone tissue in mice.The effects of Fbxw7 gene on the bone tissue components of osteoblasts were analyzed by Trap staining,Ocn staining and ALP staining.In addition,the effects of Fbxw7 gene in osteoblasts on protein pathway in mouse bone tissue were investigated by QPCR,western blot and immunohistochemistry.Through the above experimental methods,it is demonstrated whether the Fbxw7 gene is involved in the bone metabolism process.Since osteoblasts are a key component of the bone marrow hematopoietic micro environment in mature individuals,changes in osteoblast function are associated with a variety of blood-related diseases.Therefore,this study also observes Hematopoietic function of Bglap-Fbxw7 mice by flow cytometry and blood routineThe main experimental results are as follows:1.Fbxw7 gene is involved in the process of bone metabolism2.After the osteoblast knocked out the Fbxw7 gene,the body weight and body length of the mice did not change,but the number of trabecular bone in the knockout group and the trabecular bone thickness increased significantly.3.After the osteoblasts knocked out the Fbxw7 gene,the number of osteoblasts increased,which in turn affected bone metabolism.4.After the osteoblast knocked sut the Fbxw7 gene,the PCNA protein increased,the Runx2 protein decreased,the osteoblast proliferation increased,and the osteoblast differentiation decreased,which in turn affected bone metabolism.In summary,our study showed that:Fbxw7 gene is involved in bone metabolism,knocking out Fbxw7 gene in osteoblasts,which will increase the number of trabecular bone,increase the thickness of trabecular bone,increase the proliferation of osteoblasts,and osteogenesis,and the cell differentiation is reduced,and the number of osteoblasts is increased.It is suggested that the Fbxw7 gene may be a potential target in the future prevention and treatment of bone diseases.