Flag IP Spt7 -ve IgG purified Spt8 Gcn5 Ada2 Ubp8 Taf5 4741 250 SA Spt3 150 1 2 F3 8 3 4 5 6 9 7 SL SA SL F3 16 0 1 2 3 4 Anti-myc Ab A B 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Fraction SAG A SLIK Form 3 670 kD a void 158 kD a Densometry C SA SL F3 TAP-Flag Spt7 - + - + 250- 150- spt70 SPT7 1 2 D