Journal: Molecular & Cellular Proteomics : MCP
Article Title: Spinal Cord Phosphoproteome of SCA2 Mouse Model Reveals Alteration of ATXN2-N-Term PRM–SH3–Actin Interactome and of Autophagy
doi: 10.1016/j.mcpro.2025.101072
Figure Lengend Snippet: Quantitative immunoblots ( A , C , E , G , I , N = 5 or 4 versus 5) and quantitative reverse-transcriptase real-time PCR ( B , D , F , H , J , N = 6 versus 6) for SQSTM1 ( A , B ), NBR1 ( C , D ), and OPTN ( E , F ) as main aggrephagy receptors, as well as MYO6 ( G , H ) and SPARCL1 ( I , J ) in end-stage spinal cord from our SCA2–ALS13 mouse model Atxn2 -CAG100-KnockIn (KIN) versus WT. SQSTM1 and NBR1 were chosen in view of their hyperphosphorylated peptides, OPTN in view of its mix of hyperphosphorylations and hypophosphorylations, together with its interactor MYO6, and SPARCL1 in view of its many hypophosphorylated peptides. The protein changes are reflected by similar transcript upregulation for SQSTM1, versus downregulation for SPARCL1, but the MYO6 protein accumulation is counteracted by downregulation of Myo6 mRNA—a possible correlate of deficient autophagosome fusion with lysosomes. ∗ p < 0.05; ∗∗ p < 0.01, ∗∗∗ p < 0.001, and ∗∗∗∗ p < 0.0001, ns, not significant. ALS, amotrophic lateral sclerosis; MYO6, unconventional myosin VI; OPTN, optineurin; SCA2, spinocerebellar ataxia type 2; SPARCL1, secreted protein acidic and cysteine rich-like 1.
Article Snippet: The gene expression TaqMan assays (Thermo Fisher Scientific) used for this study were Bnip3 (Mm00833810_g1), Ctsb (Mm01310506_m1), Myo6 (Mm00500651_m1), Nbr1 (Mm01249798_m1), Optn (Mm01333245_m1), Ppia (Mm02342430_g1), Sparcl1 (Mm00447784_m1), Sqstm1 (Mm00448091_m1), Tax1bp1 (Mm00518038_m1), Ubqln2 (Mm00834570_s1), Wdfy3 (Mm00556380_m1), and Wnk1 (Mm01184014_m1, Mm01184007_m1, and Mm01184011_m1).
Techniques: Western Blot, Reverse Transcription, Real-time Polymerase Chain Reaction, Knock-In