Journal: bioRxiv

Article Title: Small molecule modulators targeting the interactions of small GTPase ARF1 with C9orf72:SMCR8:WDR41 complexes implicated in ALS/FTD

doi: 10.64898/2026.01.24.701325

Figure Lengend Snippet: (A) 3D structural illustration of ARF1-CSW complex and its binding pocket (ARF1 protein is in transparent cyan, SMCR8 and C9orf72 proteins are in orange and green as well as WDR41 is shown in red color (PDB: 7MGE)). The C9orf72 and SMCR8 include both longin and DEN domains. The purple circle shows the binding pocket at the interface of ARF1-CSW complex. (B) A zoomed-in view of the protein structures highlighting the key residues involved in the binding pocket at interface of ARF1 and CSW complex. (C) STRING analysis revealed the interaction network of ARF1and proteins in CSW complex including C9orf72, SMCR8 and WRD41 proteins. Line thickness indicates the strength of data support. (D) Table summarizing the functional roles of the proteins in the network, their corresponding interaction scores with ARF1 from STRING analysis, and their involvement in neurodegenerative diseases.

Article Snippet: Recombinant human ARF1 protein (Creative Biomart Inc, Shirley, NY) in Tris solution (20 mM, pH 7.4) at a concentration of 1 mg/mL was diluted to 50 μg/mL with sodium acetate buffer (pH 4.0).

Techniques: Binding Assay, Functional Assay

Journal: bioRxiv

Article Title: Small molecule modulators targeting the interactions of small GTPase ARF1 with C9orf72:SMCR8:WDR41 complexes implicated in ALS/FTD

doi: 10.64898/2026.01.24.701325

Figure Lengend Snippet: ( A ) Superimpose of identified compounds MCULE-5095997944 , MCULE-2336465708 and MCULE-5055852153 into ARF1-CSW complex proteins (ARF1 protein is in transparent cyan, SMCR8 and C9orf72 proteins are in orange and green as well as WDR41 is shown in red color (PDB: 7MGE)). Identified compounds show different poses with a certain extent of overlap with each other. (B-D) 3D representation of identified compounds interactions with ARF1-CSW complex proteins. MCULE-5095997944 (yellow), MCULE-2336465708 (red) and MCULE-5055852153 (green) bind to interface of ARF1, C9orf72, SMCR8 via different interactions such as hydrogen bonds with Ile 49 , Gly 50 of ARF1 and Pro 107 of SMCR8, as well as π-π interaction with His 5 of C9orf72.

Article Snippet: Recombinant human ARF1 protein (Creative Biomart Inc, Shirley, NY) in Tris solution (20 mM, pH 7.4) at a concentration of 1 mg/mL was diluted to 50 μg/mL with sodium acetate buffer (pH 4.0).

Techniques:

Journal: bioRxiv

Article Title: Small molecule modulators targeting the interactions of small GTPase ARF1 with C9orf72:SMCR8:WDR41 complexes implicated in ALS/FTD

doi: 10.64898/2026.01.24.701325

Figure Lengend Snippet: Binding response of (A) MCULE-5095997944, (B) MCULE-5055852153, (C) MCULE-2336465708 and (D) ZCL278 to the purified ARF1 protein using multi-cycle kinetics model and varying concentrations of 4.88 nm to 1.25 µM. (E) Evaluation software provided the corresponding kinetics and affinity data for each compound.

Article Snippet: Recombinant human ARF1 protein (Creative Biomart Inc, Shirley, NY) in Tris solution (20 mM, pH 7.4) at a concentration of 1 mg/mL was diluted to 50 μg/mL with sodium acetate buffer (pH 4.0).

Techniques: Binding Assay, Purification, Software

Journal: bioRxiv

Article Title: Small molecule modulators targeting the interactions of small GTPase ARF1 with C9orf72:SMCR8:WDR41 complexes implicated in ALS/FTD

doi: 10.64898/2026.01.24.701325

Figure Lengend Snippet: Effects of MCULE-5095997944, MCULE-2336465708, MCULE-5055852153, GDPNP and BFA (50 µM) on the Golgi in HEK293 cells. Cells were fixed and stained with anti-GM130 antibody (Red). Cell nucleus was stained with DAPI (Blue). Immunofluorescent staining of GM130 in (A) Control HEK293 cells, (B) Cells treated with BFA, (C) 50uM of MCULE-5095997944, (D) 50 uM MCULE-5055852153, (E) 50 uM MCULE-2336465708 (F) GDPNP, (G) 50 uM GDPNP followed by BFA, (H) 50 uM GDPNP followed by MCULE-5095997944. Arrows point to perinuclear Golgi. Arrowheads point to dispersed Golgi in cytoplasm. Bar: 30 um (I) Bar graph showing percent dispersion of Golgi apparatus with and without all the treatments. The mean percent Golgi apparatus dispersion was compared. (J) G-LISA analysis of ARF1-GTP levels in HEK293 cells treated with MCULE-5095997944 (100 µM) and BFA for 15 min. All data are presented as mean ± SEM from duplicates from three independent experiments. ANOVA compared treatments to their respective control ( P -values *** p < 0.01, **** p < 0.0001 were considered significant).

Article Snippet: Recombinant human ARF1 protein (Creative Biomart Inc, Shirley, NY) in Tris solution (20 mM, pH 7.4) at a concentration of 1 mg/mL was diluted to 50 μg/mL with sodium acetate buffer (pH 4.0).

Techniques: Staining, Control, Dispersion

Journal: bioRxiv

Article Title: Small molecule modulators targeting the interactions of small GTPase ARF1 with C9orf72:SMCR8:WDR41 complexes implicated in ALS/FTD

doi: 10.64898/2026.01.24.701325

Figure Lengend Snippet: (A) 3D structural illustration of ARF1-CSW complex and its binding pocket (ARF1 protein is in transparent cyan, SMCR8 and C9orf72 proteins are in orange and green as well as WDR41 is shown in red color (PDB: 7MGE)). The C9orf72 and SMCR8 include both longin and DEN domains. The purple circle shows the binding pocket at the interface of ARF1-CSW complex. (B) A zoomed-in view of the protein structures highlighting the key residues involved in the binding pocket at interface of ARF1 and CSW complex. (C) STRING analysis revealed the interaction network of ARF1and proteins in CSW complex including C9orf72, SMCR8 and WRD41 proteins. Line thickness indicates the strength of data support. (D) Table summarizing the functional roles of the proteins in the network, their corresponding interaction scores with ARF1 from STRING analysis, and their involvement in neurodegenerative diseases.

Article Snippet: The active GTP bound ARF1 levels didn’t change significantly following treatment with these compounds although at 50 μM, MCULE-5095997944 elicited a moderate but statistically insignificant increase in GTP-bound ARF1.

Techniques: Binding Assay, Functional Assay

Journal: bioRxiv

Article Title: Small molecule modulators targeting the interactions of small GTPase ARF1 with C9orf72:SMCR8:WDR41 complexes implicated in ALS/FTD

doi: 10.64898/2026.01.24.701325

Figure Lengend Snippet: ( A ) Superimpose of identified compounds MCULE-5095997944 , MCULE-2336465708 and MCULE-5055852153 into ARF1-CSW complex proteins (ARF1 protein is in transparent cyan, SMCR8 and C9orf72 proteins are in orange and green as well as WDR41 is shown in red color (PDB: 7MGE)). Identified compounds show different poses with a certain extent of overlap with each other. (B-D) 3D representation of identified compounds interactions with ARF1-CSW complex proteins. MCULE-5095997944 (yellow), MCULE-2336465708 (red) and MCULE-5055852153 (green) bind to interface of ARF1, C9orf72, SMCR8 via different interactions such as hydrogen bonds with Ile 49 , Gly 50 of ARF1 and Pro 107 of SMCR8, as well as π-π interaction with His 5 of C9orf72.

Article Snippet: The active GTP bound ARF1 levels didn’t change significantly following treatment with these compounds although at 50 μM, MCULE-5095997944 elicited a moderate but statistically insignificant increase in GTP-bound ARF1.

Techniques:

Journal: bioRxiv

Article Title: Small molecule modulators targeting the interactions of small GTPase ARF1 with C9orf72:SMCR8:WDR41 complexes implicated in ALS/FTD

doi: 10.64898/2026.01.24.701325

Figure Lengend Snippet: Binding response of (A) MCULE-5095997944, (B) MCULE-5055852153, (C) MCULE-2336465708 and (D) ZCL278 to the purified ARF1 protein using multi-cycle kinetics model and varying concentrations of 4.88 nm to 1.25 µM. (E) Evaluation software provided the corresponding kinetics and affinity data for each compound.

Article Snippet: The active GTP bound ARF1 levels didn’t change significantly following treatment with these compounds although at 50 μM, MCULE-5095997944 elicited a moderate but statistically insignificant increase in GTP-bound ARF1.

Techniques: Binding Assay, Purification, Software

Journal: bioRxiv

Article Title: Small molecule modulators targeting the interactions of small GTPase ARF1 with C9orf72:SMCR8:WDR41 complexes implicated in ALS/FTD

doi: 10.64898/2026.01.24.701325

Figure Lengend Snippet: Effects of MCULE-5095997944, MCULE-2336465708, MCULE-5055852153, GDPNP and BFA (50 µM) on the Golgi in HEK293 cells. Cells were fixed and stained with anti-GM130 antibody (Red). Cell nucleus was stained with DAPI (Blue). Immunofluorescent staining of GM130 in (A) Control HEK293 cells, (B) Cells treated with BFA, (C) 50uM of MCULE-5095997944, (D) 50 uM MCULE-5055852153, (E) 50 uM MCULE-2336465708 (F) GDPNP, (G) 50 uM GDPNP followed by BFA, (H) 50 uM GDPNP followed by MCULE-5095997944. Arrows point to perinuclear Golgi. Arrowheads point to dispersed Golgi in cytoplasm. Bar: 30 um (I) Bar graph showing percent dispersion of Golgi apparatus with and without all the treatments. The mean percent Golgi apparatus dispersion was compared. (J) G-LISA analysis of ARF1-GTP levels in HEK293 cells treated with MCULE-5095997944 (100 µM) and BFA for 15 min. All data are presented as mean ± SEM from duplicates from three independent experiments. ANOVA compared treatments to their respective control ( P -values *** p < 0.01, **** p < 0.0001 were considered significant).

Article Snippet: The active GTP bound ARF1 levels didn’t change significantly following treatment with these compounds although at 50 μM, MCULE-5095997944 elicited a moderate but statistically insignificant increase in GTP-bound ARF1.

Techniques: Staining, Control, Dispersion