FIG. 3.

Spt2 is preferentially localized to transcribed regions of active genes. (A) Spt2-13Myc is recruited to the transcribed regions of GAL1 upon galactose induction. Yeast cells from the untagged strain (FY1856) or a strain expressing Spt2-13Myc (FY2427) were grown in YPraf medium. Cells were either formaldehyde fixed or shifted to YPgal medium for 2 hours prior to formaldehyde treatment. Chromatin immunoprecipitations were then performed using the A14 anti-Myc antibody. The horizontal bars in the diagram represent the regions assayed by PCR. The fold enrichment is calculated as the ratio of percent IP of the indicated region to percent IP of a nontranscribed control region. The values shown represent the averages and standard errors from three independent experiments. (B) Spt2 is associated with the transcribed region of PMA1. Yeast cells from an untagged strain (FY1856) or a strain expressing an Spt2-13Myc epitope-tagged protein (FY2427) were grown in YPD and cross-linked with 1% formaldehyde. Chromatin immunoprecipitations were performed using the A14 anti-Myc antibody to immunoprecipitate Spt2-13Myc and the 8WG16 antibody to immunoprecipitate Rpb1. The horizontal bars in the diagram represent the regions assayed by PCR. The fold enrichment is the ratio of percent IP of the indicated region to percent IP of the control region. The values shown represent the averages and standard errors from three independent experiments. UAS, upstream activation sequence. (C) Spt2 is associated with a transcribed region of PDC1. Growth and chromatin immunoprecipitation were performed as described for panel B.