Files in this Data Supplement:

• Supplemental file 1 - Fig. S1 (Expression levels of various splicing regulatory proteins in resting and stimulated nuclear extracts)
  Zipped PDF document, 128K.
• Supplemental file 2 - Fig. S2 (Further analysis of hnRNP L and controls by 2D gels)
  Zipped PDF document, 206K.
• Supplemental file 3 - Fig. S3 (Further supporting data for Fig. 2)
  Zipped PDF document, 262K.
• Supplemental file 4 - Fig. S4 (ESS1 RNA affinity purification and binding of the previously published members of the ESS1 binding complex)
  Zipped PDF document, 229K.
• Supplemental file 5 - Fig. S5 (Controls for the specificity of PSF antibody effect on splicing)
  Zipped PDF document, 484K.