Journal: Redox Biology
Article Title: LDB1 represses fetal hemoglobin expression by enhancing BCL11A transcription
doi: 10.1016/j.redox.2026.104070
Figure Lengend Snippet: The LDB1 complex containing LMO2 and GATA1 directly enhances the transcription of the Bcl11a gene. ( A-E ) ChIP-qPCR assays were performed to assess the occupancy of putative LDB1 complex component proteins, including LDB1, LMO2, GATA1, TAL1, and E2A, at the Bcl11a locus in E14.5 WT and KO FLCs. n = 3. Control, isotype control Ab; LDB1, anti-LDB1 Ab; LMO2, anti-LMO2 Ab; GATA1, anti-GATA1 Ab; TAL1, anti-TAL1 Ab, E2A, anti-E2A Ab; WT, E14.5 FLCs; KO, E14.5 KO FLCs. Statistical significance was assessed by one-way ANOVA with Tukey HSD analysis. Mean values not sharing the same superscript letter ( a, b ) differ significantly at P < 0.05. ( F and G ) Dual-luciferase reporter assays were performed using the 210 bp region covering primer #3 ( Bcl11a intron #3) or the 225 bp region covering primer #4 ( Bcl11a intron #4) at Bcl11a locus. The relative luciferase activity of each construct containing either Bcl11a intron #3 or Bcl11a intron #4 was measured in HEK293T cells transfected with the indicated combination of each expression vector encoding Ldb1 , Lmo2 , or Gata1 cDNA. The schematic diagrams of each cloned enhancer region ( F ) and the results of the luciferase reporter assays ( G ) are presented. Ldb1 , expression vector encoding Ldb1 cDNA; Lmo2 , expression vector encoding Lmo2 cDNA; Gata1 , expression vector encoding Gata1 cDNA; ◯, transfected cells; ☓, untransfected cells. n = 5. Statistical significance was assessed by one-way ANOVA with Tukey HSD analysis. Mean values not sharing the same superscript letter ( a, b, c ) differ significantly at P < 0.05. ( H and I ) ChIP-qPCR assays were performed to assess LDB1 occupancy at the human BCL11A locus in K562 cells. The locations of each indicated primer set within the BCL11A locus are shown in the schematic diagram ( H ) along with the corresponding ChIP-qPCR results ( I ). n = 3. Mock K562, empty vector transfected K562 cells; KO K562, human LDB1 knockout K562 cells; Control, isotype control Ab; LDB1, anti-LDB1 Ab. Statistical significance was assessed by two-tailed Student's t -test. ∗ P < 0.05. All data are presented as the mean ± SEM.
Article Snippet: Sheared chromatin was immunoprecipitated using 2 μg of the following Abs per sample: anti-LDB1 (Santa Cruz Biotechnology sc-365074) and its isotype control (R&D Systems MAB004), anti-GATA1 (Santa Cruz Biotechnology sc-265) and its isotype control (Santa Cruz Biotechnology, Inc. sc-3883), anti-TAL1 (Santa Cruz Biotechnology sc-393287), anti-LMO2 (Santa Cruz Biotechnology sc-65736), anti-E2A (Santa Cruz Biotechnology sc-416) and their isotype control (Thermo Fisher Scientific 14-4714-85).
Techniques: ChIP-qPCR, Control, Luciferase, Activity Assay, Construct, Transfection, Expressing, Plasmid Preparation, Clone Assay, Knock-Out, Two Tailed Test