ZNF606 interacts with Sox9 to regulate chondrocyte differentiation

Effect of quercetin on chondrocyte phenotype and extracellular matrix expression

Due to the poor repair ability of cartilage tissue, regenerative medicine still faces great challenges in the repair of large articular cartilage defects. Quercetin is widely applied as a traditional Chinese medicine in tissue regeneration including liver, bone and skin tissues. However, the evidence for its effects and internal mechanisms for cartilage regeneration are limited. In the present study, the effects of quercetin on chondrocyte function were systematically evaluated by CCK8 assay, PCR assay, cartilaginous matrix staining assays, immunofluorescence assay, and western blotting. The results showed that quercetin significantly up-regulated the expression of chondrogenesis genes and stimulated the secretion of GAG (glycosaminoglycan) through activating the ERK, P38 and AKT signalling pathways in a dose-dependent manner. Furthermore, in vivo experiments revealed that quercetin-loaded silk protein scaffolds dramatically stimulated the formation of new cartilage-like tissue with higher histological scores in rat femoral cartilage defects. These data suggest that quercetin can effectively stimulate chondrogenesis in vitro and in vivo, demonstrating the potential application of quercetin in the regeneration of cartilage defects.

Dynamic genetic regulation of gene expression during cellular differentiation

Genetic regulation of gene expression is dynamic, as transcription can change during cell differentiation and across cell types. We mapped expression quantitative trait loci (eQTLs) throughout differentiation to elucidate the dynamics of genetic effects on cell type-specific gene expression. We generated time-series RNA sequencing data, capturing 16 time points during the differentiation of induced pluripotent stem cells to cardiomyocytes, in 19 human cell lines. We identified hundreds of dynamic eQTLs that change over time, with enrichment in enhancers of relevant cell types. We also found nonlinear dynamic eQTLs, which affect only intermediate stages of differentiation and cannot be found by using data from mature tissues. These fleeting genetic associations with gene regulation may explain some of the components of complex traits and disease. We highlight one example of a nonlinear eQTL that is associated with body mass index.

Association of expression of ZNF606 gene from monocytes with the risk of coronary artery disease

AIM

Messenger RNAs (mRNAs) play an important role in the pathogenesis of coronary artery disease (CAD). We evaluated the association of selected increase in mRNAs from monocytes with the risk of CAD.

METHODS

Chip data (GSE9820) retrieved from Gene Expression Omnibus (GEO) was re-analyzed, and the selected candidate genes, meeting specific conditions, were up-regulated and verified for specific biomarkers of CAD within a prospective cohort study that recruited 194 individuals and subdivided into two groups: group Non-CAD (GN), n = 68 and group CAD (GC), n = 126. The patients in GC were further categorized into three sub-units according to the extent of coronary stenosis shown during coronary angiography, coded as single-vessel stenosis (GC1, n = 53), 2-vessel stenosis (GC2, n = 50), or ≥ 3-vessel stenosis (GC3, n = 23). All candidate mRNAs expressions were analyzed from patients' monocytes with quantitative PCR (q-PCR). Receiver-operating characteristic (ROC) curves and the area under the ROC curves (AUCs) were used to evaluate the mRNAs' feasibility for CAD prediction. AUCs ≥0.8 were accounted as highly specific association with CAD.

RESULTS

GBA2, CSTF3, ZNF606 and MPP5 were selected as mRNAs candidates from chip data reanalysis. GBA2 (P = .002) and ZNF606 (P < .001) expressions were significantly increased in GC. ZNF606 showed significant increase after adjusting the risk factors with logistic regression analysis (OR = 3.804, 95% CI: 1.923, 7.798, P < .001), and its expression level was positively correlated with age (β = 0.04 × 10^-3, P < .001). The AUCs (and 95% CI) of ZNF606 expression in GC2 and GC3 were ≥0.8.

CONCLUSION

These findings suggest that it is novel and specific for the association of ZNF606 gene expression from monocytes with the risk of CAD, especially in patients with multiple coronary artery stenosis.