Journal: Autophagy

Article Title: Evidence of an unprecedented cytoplasmic function of DDX11, the Warsaw breakage syndrome DNA helicase, in regulating autophagy

doi: 10.1080/15548627.2025.2507617

Figure Lengend Snippet: Autophagy is impaired in WABS patient and DDX11 KO RPE-1 cells. (A) Fibroblasts from three different WABS patients and from a healthy donor (HF1) were left in full medium or serum starved for 16 h. LC3-II level was assessed by western blot analysis. TUBA/tubulin was used as a loading control. (B) Graphs show the quantifications of LC3-II:TUBA. (C,D) fibroblasts from three different WABS patients and from a healthy donor (HF1) were treated with BAF A 1 for 16 h. LC3-II level was assessed by western blot analysis. TUBA was used as loading control. Graphs show the quantifications of LC3-II:TUBA. (E) RNA-seq analysis shows no difference in transcripts per kilobase million/TPM of autophagy genes ( ATG16L1 , ATG5 , ATG12 , BECN1 , SQSTM1 ) between control (CTRL) and DDX11 KO ( DDX11 KO) RPE-1 cells. (F) Western blot analysis revealed no difference in the expression level of the indicated autophagy proteins between control (CTRL) and DDX11 KO ( DDX11 KO) RPE-1 cells. TUBA was used as loading control. (G,H) control (CTRL) and DDX11 KO ( DDX11 KO) RPE-1 cells were grown in full-medium (FM) or serum starved for 16 h (NO FBS). LC3-II was analyzed by western blot. TUBA was used as loading control. Graphs show the quantifications of LC3-II:TUBA. (I,J) Control (CTRL) and DDX11 KO ( DDX11 KO) RPE-1 cells were treated with DMSO or BAF A 1 for 6 h. LC3-II level was analyzed by western blot. TUBA was used as loading control. Graphs show the quantifications of LC3-II:TUBA. (K–M) DDX11 KO (KO) RPE-1 cells were transfected with a vector expressing DDX11-Flag wild-type protein (WT) or the DDX11-Flag K50R helicase-dead mutant (K50R) to perform rescue experiments. After 24 h, control (CTRL), DDX11 KO ( DDX11 KO) and DDX11-complemented DDX11 KO (KO + WT and KO + K50R) RPE-1 cells were treated with DMSO or BAF A 1 for 6 h. LC3 level (LC3-I and LC3-II) was analyzed by western blot. Graphs show the quantifications of LC3-II:TUBA. (N) Control (CTRL) and DDX11 KO ( DDX11 KO) RPE-1 cells were transfected with a vector expressing EGFP-HTT-74Q for 48 h to assess HTT mutant protein clearance. (O) Graph shows increased percentage of HTT-positive cells in the DDX11 KO RPE-1 line. Number of cells counted n = 50 in triplicates. Scale bar: 10 µm.

Article Snippet: The following antibodies were used: mouse monoclonal anti DDX11 (Santa Cruz Biotechnology, sc271711); mouse monoclonal anti-Flag antibody (Merck, F1804); rabbit polyclonal anti-LC3 (Novus Biologicals, NB100–2220); mouse monoclonal anti-LAMP1 (Cell Signaling Technology, 15665); rabbit polyclonal anti-SQSTM1 (MBL International, PM045); mouse monoclonal anti-TUBA/α-tubulin antibody (Merck, T6199); rabbit polyclonal anti-ATG16L1 antibody (MBL Life Sciences, PM040); rabbit monoclonal anti-ATG5 antibody (Cell Signaling Technology, 129945); rabbit polyclonal anti-BECN1/BECLIN1 antibody (Cell Signaling Technology, 3738S); rabbit polyclonal anti-AKT antibody (Cell Signaling Technology, 9272S); rabbit polyclonal anti-phospho-AKT (Ser473) antibody (Cell Signaling Technology, 9271 L); rabbit polyclonal anti-BRIP1/FANCJ antibody (Novus Biologicals, NBP1–31883); mouse monoclonal anti-histone H3 antibody (Abcam, ab24834); rabbit monoclonal anti-GFP antibody (Cell Signaling Technology, 2956); mouse and rabbit HRP-conjugated secondary antibody (Merck, A9044 and 12–348, respectively); Alexa Fluor 488 anti-rabbit antibody, Alexa Fluor 555 anti-mouse antibody and Alexa Fluor 633 anti-mouse antibody (Thermo Fisher Scientific, A-11008, A-21137, A-21146, respectively).

Techniques: Western Blot, Control, RNA Sequencing, Expressing, Transfection, Plasmid Preparation, Mutagenesis

Journal: Autophagy

Article Title: Evidence of an unprecedented cytoplasmic function of DDX11, the Warsaw breakage syndrome DNA helicase, in regulating autophagy

doi: 10.1080/15548627.2025.2507617

Figure Lengend Snippet: DDX11 regulates ATG16L1 localization. (A,B) Control (CTRL), DDX11 KO ( DDX11 KO) and DDX11-complemented DDX11 KO ( DDX11 KO + WT DDX11 ) RPE-1 cells were transfected with ATG16L1-GFP for 24 h. Confocal imaging shows accumulation of ATG16L1 in the perinuclear area that was reverted by re-expressing the DDX11-Flag wild-type protein. Total cells analyzed: n = 50 per experiment, performed in triplicates. Scale bar: 10 µm. (C) Co-immunoprecipitation experiment using an anti-ATG16 antibody in control (CTRL) and DDX11 KO RPE-1 cells. Western blot analysis shows co-immunoprecipitation of ATG5-ATG12 in both control and DDX11 KO ( DDX11 KO) RPE-1 cells indicating that, in the absence of DDX11, the ATG12–ATG5-ATG16L1 complex formation is not affected. Asterisks denote the IgG heavy chains. (D) Control (CTRL), DDX11 KO ( DDX11 KO) and DDX11-complemented DDX11 KO ( DDX11 KO + WT DDX11 ) RPE-1 cells were transfected with a vector expressing GFP-ATG16L1 for 48 h. Co-immunoprecipitation experiment was performed using anti-GFP antibody conjugated beads. The indicated proteins were detected by western blot of the pulled-down sample using specific antibodies. (E) Control (CTRL), DDX11 KO ( DDX11 KO) and DDX11-complemented DDX11 KO ( DDX11 KO + WT DDX11 ) RPE-1 cells were transfected with GFP-ATG16L1 and mCherry-LC3 for 24 h. Then, cells were processed as described for panel A. Confocal imaging reveals that ATG16L1 and LC3 do not colocalize in DDX11 KO cells. This phenotype is reversed by re-expressing the DDX11-Flag wild-type protein. Scale bar: 10 µm.

Article Snippet: The following antibodies were used: mouse monoclonal anti DDX11 (Santa Cruz Biotechnology, sc271711); mouse monoclonal anti-Flag antibody (Merck, F1804); rabbit polyclonal anti-LC3 (Novus Biologicals, NB100–2220); mouse monoclonal anti-LAMP1 (Cell Signaling Technology, 15665); rabbit polyclonal anti-SQSTM1 (MBL International, PM045); mouse monoclonal anti-TUBA/α-tubulin antibody (Merck, T6199); rabbit polyclonal anti-ATG16L1 antibody (MBL Life Sciences, PM040); rabbit monoclonal anti-ATG5 antibody (Cell Signaling Technology, 129945); rabbit polyclonal anti-BECN1/BECLIN1 antibody (Cell Signaling Technology, 3738S); rabbit polyclonal anti-AKT antibody (Cell Signaling Technology, 9272S); rabbit polyclonal anti-phospho-AKT (Ser473) antibody (Cell Signaling Technology, 9271 L); rabbit polyclonal anti-BRIP1/FANCJ antibody (Novus Biologicals, NBP1–31883); mouse monoclonal anti-histone H3 antibody (Abcam, ab24834); rabbit monoclonal anti-GFP antibody (Cell Signaling Technology, 2956); mouse and rabbit HRP-conjugated secondary antibody (Merck, A9044 and 12–348, respectively); Alexa Fluor 488 anti-rabbit antibody, Alexa Fluor 555 anti-mouse antibody and Alexa Fluor 633 anti-mouse antibody (Thermo Fisher Scientific, A-11008, A-21137, A-21146, respectively).

Techniques: Control, Transfection, Imaging, Expressing, Immunoprecipitation, Western Blot, Plasmid Preparation

Journal: Autophagy

Article Title: Evidence of an unprecedented cytoplasmic function of DDX11, the Warsaw breakage syndrome DNA helicase, in regulating autophagy

doi: 10.1080/15548627.2025.2507617

Figure Lengend Snippet: Schematic model describing a putative role of DDX11 in autophagy pathway regulation. DDX11 exerts its function as a DNA helicase in the nuclear compartment. Within the cytoplasm, DDX11 cooperates with SQSTM1 and ATG16L1 to promote phagophore formation as well as the autophagic flux (bold green and blue dotted arrows, respectively; left side ). Absence of DDX11 affects intracellular localization of the ATG16L1 autophagy precursor, which in turn impairs LC3 lipidation and autophagosome fusion with lysosomal compartment, ultimately reducing the autophagic flux (thin green and blue dotted arrows, respectively; right side ).

Article Snippet: The following antibodies were used: mouse monoclonal anti DDX11 (Santa Cruz Biotechnology, sc271711); mouse monoclonal anti-Flag antibody (Merck, F1804); rabbit polyclonal anti-LC3 (Novus Biologicals, NB100–2220); mouse monoclonal anti-LAMP1 (Cell Signaling Technology, 15665); rabbit polyclonal anti-SQSTM1 (MBL International, PM045); mouse monoclonal anti-TUBA/α-tubulin antibody (Merck, T6199); rabbit polyclonal anti-ATG16L1 antibody (MBL Life Sciences, PM040); rabbit monoclonal anti-ATG5 antibody (Cell Signaling Technology, 129945); rabbit polyclonal anti-BECN1/BECLIN1 antibody (Cell Signaling Technology, 3738S); rabbit polyclonal anti-AKT antibody (Cell Signaling Technology, 9272S); rabbit polyclonal anti-phospho-AKT (Ser473) antibody (Cell Signaling Technology, 9271 L); rabbit polyclonal anti-BRIP1/FANCJ antibody (Novus Biologicals, NBP1–31883); mouse monoclonal anti-histone H3 antibody (Abcam, ab24834); rabbit monoclonal anti-GFP antibody (Cell Signaling Technology, 2956); mouse and rabbit HRP-conjugated secondary antibody (Merck, A9044 and 12–348, respectively); Alexa Fluor 488 anti-rabbit antibody, Alexa Fluor 555 anti-mouse antibody and Alexa Fluor 633 anti-mouse antibody (Thermo Fisher Scientific, A-11008, A-21137, A-21146, respectively).

Techniques: