Journal: MedComm
Article Title: SEMA3B‐AS1 suppresses colorectal carcinoma progression by inhibiting Semaphorin 3B‐dependent VEGF signaling pathway activation
doi: 10.1002/mco2.365
Figure Lengend Snippet: SEMA3B‐AS1 promotes the expression of SEMA3B by recruiting EP300 to accelerate histone H3 acetylation. (A) Nuclear‐enriched SEMA3B‐AS1 was determined by fluorescence in situ hybridization (left) and RNA fraction assays (right). (B) RIP experiments were performed in HCT116 cells using an EP300 or nonspecific IgG antibody to determine the amount of SEMA3B‐AS1 RNA associated with EP300 or IgG relative to the input control. (C) RNA pull‐down assays were used to identify proteins associated with SEMA3B‐AS1 . Biotinylated SEMA3B‐AS1 and antisense RNA were incubated with cell extracts, and the associated proteins were resolved by SDS–PAGE. Western blotting was performed to analyze the specific interaction between EP300 and SEMA3B‐AS1 . Dot blot of RNA–protein binding samples indicates equal RNA transcripts present in the assay. (D) SEMA3B‐AS1 did not affect EP300 mRNA expression levels (left), but SEMA3B‐AS1 overexpression significantly increased the protein levels of EP300, H3K9ac, and SEMA3B (right). (E and F) EP300 can bind to the SEMA3B promoter. A schematic illustration of the SEMA3B‐AS1 and SEMA3B structures is shown (E, top). Arrows show the direction of transcription. The numbered sites denote the promoter fragments of the SEMA3B gene. The ability of EP300 to bind to SEMA3B promoter regions was assessed by chromatin immunoprecipitation (ChIP) (E) and was increased as a result of SEMA3B‐AS1 overexpression (F). White arrow shows the SEMA3B promoter region that EP300 binds to (E). (G) Depletion of EP300 mediated by siRNA significantly decreased H3K9 acetylation and SEMA3B protein levels in colorectal carcinoma cell lines overexpressing SEMA3B‐AS1 . (H) SEMA3B mRNA was regulated by the histone deacetylase inhibitor TSA and acetyltransferase inhibitor C646 in colorectal carcinoma cells. The C646 and TSA double‐negative group was set as control. (I) SEMA3B protein was regulated by the histone deacetylase inhibitor TSA and acetyltransferase inhibitor C646 in colorectal carcinoma cells. * p < 0.05; ** p < 0.01; *** p < 0.001.
Article Snippet: The slides were incubated at 4°C for 8 h with primary antibodies against SEMA3B (1:100, NB100‐2218SS, Novusbio) and Ki‐67 (1:500, 27309‐1‐AP, ProteinTech Group).
Techniques: Expressing, Fluorescence, In Situ Hybridization, Control, Incubation, SDS Page, Western Blot, Dot Blot, Protein Binding, Over Expression, Chromatin Immunoprecipitation, Histone Deacetylase Assay