SOX11 directly regulates PAX5 transcription. (A) Binding of SOX11 to regulatory regions of PAX5, MSI2, SEPT2, SUV39H2, and HSPD1 was confirmed by ChIP-qPCR in different MCL cell lines. Results are shown as enrichment relative to input. (B) Levels of the indicated transcripts in Z138 and GRANTA519 quantified by qRT-PCR after SOX11 silencing. Fold-change differences compared with control cells are shown. (C) Upper panel: Levels of SOX11 and PAX5 in Z138 and GRANTA519 cell lines stably transduced with shControl, shSOX11.1, or shSOX11.3 determined by WB, using GAPDH as a loading control. Lower panel: Fold-change differences of SOX11 and PAX5 protein expression levels between control and silenced cells. SOX11 and PAX5 expression levels were corrected by quantification of GAPDH expression levels. (D) Luciferase assays in transient cotransfections of PAX5 enhancer-GL4.23 Luc with SOX11 full-length, the truncated SOX11 proteins (SOX11ΔHMG and SOX11ΔCtermTAD), or SOX4 full-length expression vectors, in HEK293 cells. Upper panel: Schematic representation of the constructs and results of the WB experiment of SOX11 mutants are shown. *Nonspecific bands. Bottom panel: Results are shown as fold induction relative to luciferase activity in cotransfection with the empty vector (pcDNA3). Bar plot represents the mean ± SD of 3 independent experiments. The significance of difference was determined by paired t test. HA, hemagglutinin.