Fig 1: Upregulation of circ-Tulp4 affected the proliferation of ß cells by sponging miR-7222-3p and regulating soat1/cyclin D1 signaling. Min6 cells were transfected with miR-7222-3p mimic, or co-treated with circ-Tulp4 vector (A) or Soat1 vector (B) for 48 h, followed by PA (0.5 mM) treatment for 24 h. Cell proliferation ability was detected by MTS. (C) Min6 cells were transfected with siRNA-1 or siRNA-2 for circ-Tulp4, or co-treated with Soat1 vector for 48 h, followed by PA (0.5 mM) treatment for 24 h. Western blot assays were used to analyze the protein expression level of ki67. (D) Min6 cells were transfected with miR-7222-3p mimic, or co-treated with circ-Tulp4 vector for 48 h, followed by PA (0.5 mM) treatment for 24 h. Min6 cells were transfected with siRNA-1 or siRNA-2 for soat1 for 48 h, followed by PA (0.5 mM) treatment for 24 h. Protein expression of ki67 in indicated groups. The expression level of cyclin D1 mRNA (E) or cyclin D1 protein (F and G) in Min6 cells infected with circ-Tulp4 vector or Soat1 vector. Cell cholesterol easter content was examined after overexpressing circ-Tulp4 or Soat1 (H). GISI assay was performed to examine the insulin secretion of Min6 cells transfected with miR-7222-3p mimic, or co-treated with circ-Tulp4 vector or Soat1 vector (I). **P < 0.01 vs the NC treated group in 16.7 mmol/L glucose. #P < 0.05; ## P < 0.01 vs the miR-7222-3p mimic treated group in 16.7 mmol/L glucose. Cell cycle distribution was investigated by flow cytometry in Min6 cells infected with circ-Tulp4 vector or Soat1 vector (J). *P < 0.05; **P < 0.01; ***P < 0.001 vs the indicated groups.