Fig. 1. Autosomal insertions of roX1 or 1.688^3F recruit MSL2.

A) MSL2 recruitment (red) is limited to the X chromosome in a control male. B) Enlargement of cytological position 22A3 (yellow arrow) from A. C) [roX1]^22A3 recruits MSL2 to a single band near 22A3. D) [1.688^3F]^22A3 recruits MSL2 robustly near the integration site (yellow arrow). Spreading to a sub-telomeric region is observed (white arrow). E) MSL2 recruitment by [roX1+1.688^3F]^22A3 is robust and similar to [1.688^3F]^22A3. Yellow arrow marks the 22A3 integration site. F) Detail from E. White arrow marks sub-telomeric spreading. Scoring of MSL2 recruitment and spreading is presented in Table 1. G) Visible MSL2 recruitment (red) in a [1.688^3C]^22A3 male larvae is limited to the X chromosome. Yellow arrow marks the insertion site at 22A3. H) Robust MSL2 recruitment (yellow arrow) and spreading to a subtelomeric region (white arrow) is observed in [roX1+1.688^3C]^22A3 males. Chromosome preparations were probed with anti-MSL2 antibody and detected by Texas Red. DNA is counterstained with DAPI (blue). See also Figures S1-S3 and Figure S5.