Journal: bioRxiv
Article Title: TRIM37 employs peptide motif recognition and substrate-dependent oligomerization to prevent ectopic spindle pole assembly
doi: 10.1101/2024.10.09.617493
Figure Lengend Snippet: (A) AlphaFold model of the anti-parallel TRIM37 dimer. The RING and B-box-2 domains are on opposite ends of the dimer, and the TRAF domains are positioned just below the mid-point of the anti-parallel coiled-coil. One TRIM37 monomer is colored from the N-terminus in blue to the C-terminus in red; the second TRIM37 monomer is colored grey. See also . (B) ( left ) Schematic of TRIM37 along with an AlphaFold model of the TRAF domain highlighting the tryptophan residue (W373) that was mutated to prevent putative peptide ligand engagement (see also ). ( right ) Immunoblot of TRIM37Δ RPE1 cells engineered to express the indicated TRIM37 variants using lentiviral transduction. The TRIM37 transgenes include a FLAG tag, which is immunoblotted; α-tubulin serves as a loading control. Numbers below the lanes indicate the percentage of cells in the transduced pool that express the transgene, as assessed by anti-FLAG immunostaining. (C) & (D) Images of control and TRIM37Δ RPE1 cells ( C ) and of TRIM37Δ cells expressing the indicated TRIM37 transgenes ( D ). Cells were labeled for centrobin and DNA; centrosomes ( yellow arrows ) and condensates ( cyan arrowhead s) are indicated on the images. Centrosomes are magnified to the left of the lower magnification view and, when present, centrobin condensates to the right. (E) Frequency of centrobin condensate formation for the indicated conditions. n is the number of cells analyzed. (F) ( left ) Experimental schematic of analysis of TRIM37 interaction with centrobin following co-expression in FreeStyle 293F cells. The ligase activity of TRIM37 was mutated to enable robust expression and assessment of binding. The centrobin fragment (1-767) is soluble and contains the TRIM37-binding region (see & ), facilitating the binding analysis. ( right ) Immunoblot of Centrobin (1-767), detected using the Myc epitope tag, and TRIM37, detected using the FLAG epitope tag, in cell lysates and following anti-Myc immunoprecipitation. α-tubulin serves as a loading control for the input lysates. Scale bars in panels C and D , 5 µm ( lower magnification views ) and 1 µm ( centrosome and condensate blowups ).
Article Snippet: The TRIM37 TRAF domain coding sequence (residues 274-407) was amplified and cloned into the UC Berkeley Macrolab vector 2CT (Addgene number: 29706) to express N-terminal TEV protease-cleavable His 6 -MBP-tagged fusions.
Techniques: Residue, Western Blot, Transduction, FLAG-tag, Control, Immunostaining, Expressing, Labeling, Activity Assay, Binding Assay, Immunoprecipitation