Fig. 4.

Xio regulates Sxl alternative splicing and interacts with Sxl. (A) Model showing female- or male-specific Sxl alternative splicing mediated by the m⁶A writer and Sxl protein. Only the regulatory events in the intron downstream of exon 3 are shown. The arrows indicate the primers used for RT-PCR. (B) Sxl splicing was analyzed by RT-PCR using RNA extracted from wing discs of indicated genotypes. Male-specific bands: 2-3-4. Female-specific bands: 2-4. (C) S2 or Kc cells were treated with xio RNAi or GFP RNAi, and Sxl splicing was analyzed by RT-PCR. (D) Sxl-HA, Xio-GFP, or GFP were transfected into S2 cells. Cell lysates were IPed and analyzed by Western blot. (E) SNF-GFP or GFP and Sxl-HA, METTL3-HA, METTL14-HA, Fl(2)d-HA, Nito-HA, and Xio-HA were cotransfected into S2 cells. Cell lysates were IPed and analyzed by Western blot. While large amounts of Sxl-HA and Nito-HA were co-IPed by SNF-GFP (double asterisk), a very low amount of Fl(2)d-HA was observed (asterisk), and there are no detectable METTL3-HA, METTL14-HA, and Xio-HA from the pull down.