Why SNP rs227584 is associated with human BMD and fracture risk? A molecular and cellular study in bone cells

Abstract

A large number of SNPs significant for osteoporosis (OP) had been identified by genome‐wide association studies. However, the underlying association mechanisms were largely unknown. From the perspective of protein phosphorylation, gene expression regulation, and bone cell activity, this study aims to illustrate association mechanisms for representative SNPs of interest.We utilized public databases and bioinformatics tool to identify OP‐associated SNPs which potentially influence protein phosphorylation (phosSNPs). Associations with hip/spine BMD, as well as fracture risk, in human populations for one significant phosSNP, that is, rs227584 (major/minor allele: C/A, EAS population) located in C17orf53 gene, were suggested in prior meta‐analyses. Specifically, carriers of allele C had significant higher BMD and lower risk of low‐trauma fractures than carriers of A. We pursued to test the molecular and cellular functions of rs227584 in bone through osteoblastic cell culture and multiple assays.We identified five phosSNPs significant for OP (P < 0.01). The osteoblastic cells, which was transfected with wild‐type C17orf53 (allele C at rs227584, P126), demonstrated specific interaction with NEK2 kinase, increased expression levels of osteoblastic genes significantly (OPN, OCN, COL1A1, P < 0.05), and promoted osteoblast growth and ALP activity, in contrast to those transfected with mutant C17orf53 (allele A at rs227584, T126).In the light of the consistent evidences between the present functional study in human bone cells and the prior association studies in human populations, we conclude that the SNP rs227584, via altering protein‐kinase interaction, regulates osteoblastic gene expression, influences osteoblast growth and activity, hence to affect BMD and fracture risk in humans.

Investigation on the molecular mechanism of SPA interference with osteogenic differentiation of bone marrow mesenchymal stem cells

“…The functional enrichment analysis showed that Nek2 was mainly related to the 'autophagosome' and 'pyrimidine metabolism'. It had been shown that the over-expression of Nek2 was associated with the development of bone damage (36) and that it regulated osteoblast gene expression and affected osteoblast growth and activity (37). In addition, Nek2 induced osteoclast differentiation and bone destruction via heparanase in multiple myeloma (38).…”

Mendelian Randomization Identifies CpG Methylation Sites With Mediation Effects for Genetic Influences on BMD in Peripheral Blood Monocytes

“…C17orf53 gene was associated with BMD and fracture risk in a large genome-wide meta-analysis study, including 17 GWAS and 32,961 individuals of European and East Asian ancestry (Estrada et al, 2012). A recent study investigated the molecular and cellular functions of a specific BMD-associated SNP (rs227584) in C17orf53 gene using osteoblastic cells and demonstrated that the SNP rs227584 may alter substrate-kinase interaction between protein C17orf53 and NEK2 and subsequently regulate osteoblast growth and activity (Zhou X. et al, 2019). Our findings complement the previous results and provide further supporting evidence for the significance of C17orf53 gene on regulating BMD variation and OP risk.…”