Figure 4

Recombinant LaTRF and the mutant bearing the C-terminal Myb domain bind in vitro double-stranded telomeric DNA. Electrophoretic mobility shift assays (EMSA) were done using radiolabeled double-stranded telomeric DNA (LaTEL) as probe. Protein:DNA complexes were separated in a 4% PAGE in 1X TBE. EMSA was done with E. coli BL21 protein extract (lane 2), recombinant full length LaTRF (lanes 3-6) and a mutant bearing the C-terminal Myb domain (lanes 7-9). A supershift assay was done with anti-LaTRF serum (lane 6). Assays were also done in the presence of 20 fold excess of non-labeled LaTEL as specific competitor (lanes 4 and 8) or 100 fold excess of double-stranded non-specific poly [dI-dC] [dI-dC] DNA (lanes 5 and 9). In lane 1, no protein was added to the binding reaction. The original gel image and its content are shown as additional file 1: Figure S1.