Journal: The EMBO Journal
Article Title: LncRNA LITATS1 suppresses TGF‐β‐induced EMT and cancer cell plasticity by potentiating TβRI degradation
doi: 10.15252/embj.2022112806
Figure Lengend Snippet: Scheme for screening lncRNAs induced by TGF‐β. MCF10A‐M1, MCF10A‐M2, and MDA‐MB‐231 cells were treated without (0 h) or with TGF‐β for 2 h, 8 h, or 24 h. RNA samples (biological triplicates) were collected for RNA‐seq, and lncRNAs induced by TGF‐β were selected for further analysis. Heatmap showing the log2 fold changes in the 15 lncRNA hits induced by TGF‐β at all three time points (2 h, 8 h, and 24 h vs. 0 h) in at least two cell lines. LITATS1 expression upon SMAD4 knockdown (as detected by RT–qPCR) in MDA‐MB‐231 cells. Cells were serum starved for 16 h and TGF‐β was added for 4 h. Representative results from a minimum of three independent experiments are shown. LITATS1 expression (as detected by RT–qPCR) in HEK293T cells. Cells were transfected without (Co.vec) or with the constitutively active TGF‐β type I receptor (caTβRI) ectopic expression construct. Representative results from a minimum of three independent experiments are shown. Effect of TGF‐β on LITATS1 promoter activity as determined by luciferase reporter assays. HepG2 cells were transfected with empty pGL4 vector (Co.vec) or with two indicated LITATS1 promoter luciferase reporters ( LITATS1 ‐P1 and LITATS1 ‐P2). Cells were stimulated with ligand buffer as the vehicle control (−), BMP6 (50 ng/ml), or TGF‐β (5 ng/ml) for 16 h. Representative results from a minimum of three independent experiments are shown. Effect of caTβRI and SMAD3 on LITATS1 promoter activity as determined by luciferase reporter assays. HepG2 cells were transfected with ectopic expression constructs for the LITATS1 promoter 2 luciferase reporter ( LITATS1 ‐P2) and caTβRI or SMAD3 and were then stimulated with or without TGF‐β for 16 h. Representative results from a minimum of three independent experiments are shown. Schematic representation of the genomic location of LITATS1 and its neighboring genes. The arrows indicate the direction of transcription. CPAT software was used to predict the coding potential of protein‐coding mRNAs ( ACTB2 and GAPDH ), well‐annotated lncRNAs ( Xist and NKILA ), and LITATS1 . Expression analysis of lncRNA H19 , NEAT1 , and LITATS1 expression levels in the cytoplasmic and nuclear fractions of MCF10A‐M1, MCF10A‐M2, and MDA‐MB‐231 cells. Representative results from a minimum of three independent experiments are shown. RNA fluorescence in situ hybridization was performed to evaluate LITATS1 expression and subcellular localization in A549 cells. Cells were treated with or without TGF‐β for 2 h. Representative images are shown in the left panel, and signal quantification data are shown in the right panel. Scale bar = 10 μm. Representative results from two independent experiments are shown. Data information: TGF‐β was applied at a final concentration of 5 ng/ml. (C, D, E, F) are expressed as the mean ± SD values from three biological replicates ( n = 3). (J) is expressed as the mean ± SD values from 30 biological replicates ( n = 30). *0.01 < P < 0.05; **0.001 < P < 0.01; ***0.0001 < P < 0.001; **** P < 0.0001; NS, not significant. Statistical analysis was based on the unpaired Student's t ‐test. Source data are available online for this figure.
Article Snippet: HEK293T (CRL‐1573), HepG2 (HB‐8065), A549 (CRM‐CCL‐185), A549 (CCL‐185EMT), MDA‐MB‐231 (CRM‐HTB‐26), MDA‐MB‐436 (HTB‐130), and MCF7 (HTB‐22) cells were purchased from the American Type Culture Collection (ATCC) and cultured in Dulbecco's modified Eagle medium (DMEM; Thermo Fisher Scientific; 41965062) supplemented with 10% fetal bovine serum (FBS; Thermo Fisher Scientific; 16000044) and 100 U/ml penicillin/streptomycin (Thermo Fisher Scientific; 15140163).
Techniques: RNA Sequencing, Expressing, Knockdown, Quantitative RT-PCR, Transfection, Construct, Activity Assay, Luciferase, Plasmid Preparation, Control, Software, Fluorescence, In Situ Hybridization, Concentration Assay