Fig 1: PAFAH1B1 regulates the expression of actin-regulatory proteins by interacting with IQGAP1 in murine Sertoli cells. a-h Western blot analysis and quantification for CDC42, PAK1, LIMK1, Cofilin, and p-Cofilin proteins in miR-181c/d mimics treated murine SCs (a, b), LV-miR-181c/d treated murine testes (c, d), Pafah1b1 siRNA treated murine SCs (e, f), and miR-181c/d inhibitors + Pafah1b1 siRNA or miR-181c/d inhibitors + Cdc42 siRNA co-treated murine SCs (g, h). i The interaction between PAFAH1B1 and IQGAP1 was predicted by the ZDOCK server. PAFAH1B1 is indicated in green plus yellow; IQGAP1 is indicated in gray; the region of interaction is indicated in red. j, k Co-immunoprecipitation of PAFAH1B1 with IQGAP1 in murine SCs. l, m Immunoprecipitation assay was performed in Pafah1b1 siRNA (l) or miR-181c/d mimics (m) treated murine SCs. n A schematic diagram illustrating the regulatory roles of the miR-181c/d-PAFAH1B1 axis on the Sertoli cell barrier function. Overexpression of miR-181c/d in murine SCs inhibits PAFAH1B1, which reduces the PAFAH1B1-IQGAP1 complex, resulting in the downregulation of CDC42 and its downstream PAK1, LIMK1, and p-Cofilin. Thus, changes in the expression of these actin-regulatory proteins impede the organization of F-actin, which could be a potential reason for perturbing the stabilization of the attachment sites between BTB-associated proteins and F-actin and disturbing the Sertoli cell barrier function