TPE-OLD modifies SORBS2 expression in FSHD myoblasts. (A,B) Amplification of SORBS2 transcripts in FSHD and sibling control myoblasts with long and short telomeres. (A) RT-PCR of SORBS2 transcripts using primers amplifying all known transcript variants that include exons 17 and 42 (23 variants). Assay performed in FSHD#12 and sibling control, FSHD#11, and FSHD#15 myoblasts with long and short telomeres. Only FSHD myoblasts with short telomeres express the 2-kb splice forms (23 variants, including eight protein-coding forms). (B) RT-PCR performed using a set of primers amplifying all known transcript variants between exons 31 and 42 (a total of 30 forms). Among the 30 isoforms detected, 13 exclude the totality of exon 40 (smaller form at ∼530 bp), among which are the nine protein-coding variants. (C) Gene expression analysis of SORBS2. For all four assays, we report the predicted transcripts according to the NCBI database. ddPCR results are expressed as the number of molecules detected in a 12.5-ng RT input; values are averages ± SEM.
