Figure 9.

Full-length Hop1 and Hop1CTD, but not the N-terminal fragment of Hop1 (HORMA), exhibit efficient binding to the G-quadruplex formed by a meiosis-specific DSB from chromosome IV of S. cerevisiae. The reaction mixtures (20 μL) contained 0.5 nM ³²P-labeled G-rich ssDNA (A–C) or G4 DNA (D–F). The reaction mixtures were incubated in the absence (lane 1) or presence of (lanes 2–11) 20, 40, 60, 80, 100, 120, 140, 160, 180, and 200 nM of full-length Hop1, HORMA, or Hop1CTD, respectively. In (D)–(F), the reaction mixtures also contained 50 mM KCl. The solid triangle on top of the gel denotes increasing concentrations of the specified protein. (G) Shown here is a graphical representation of the extent of protein binding to G-rich ssDNA or G4 DNA. The extent of formation of a protein–DNA complex in (A)–(F) is plotted versus varying concentrations of the specified protein. Error bars indicate mean ± SE.