Fig. 4

The binding of KPNA2 and STAT3 was increased under hypoxia. A IP-MS of KPNA2 showed that the binding of 364 proteins to KPNA2 was increased under hypoxia compared to normoxia. Metascape was used for enrichment analysis of these proteins, and the results showed that the top three enriched pathways were RNA metabolism, ribonucleoprotein complex biogenesis, and the VEGFA-VEGFR2 pathway. B After overexpression and knockdown of KPNA2 in HUVEC under hypoxia for 12 h, changes in VEGF and P-VEGFR2 levels were detected by Western blotting, and GAPDH was used as an internal control. C We selected the top ten proteins related to the VEGFA-VEGFR2 pathway upregulated under hypoxia (IgG as a control) and the top ten proteins related to the VEGFA-VEGFR2 pathway that were found to be upregulated under hypoxia vs. normoxia identified by IP-MS analysis of KPNA2 in HUVEC and determined the intersecting proteins. We obtained three proteins, namely, GPX1, STAT3 and MOV10. D The changes in MOV10 and GPX1 levels were detected by Western blotting after overexpression or knockdown of KPNA2 in HUVEC under hypoxia for 12 h, and β-ACTIN was an internal control. E Western blotting analysis of immunoprecipitated STAT3 under normoxia vs hypoxia for 12 h was used to detect KPNA2. F IP analysis of KPNA2 under normoxia vs hypoxia for 12 h was carried out, and Western blotting was used to detect STAT3. Each experiment was repeated three times