Figure 3.

Formation of truncated forms of Spt7 in N-terminally deleted derivatives. A. N-terminally deleted derivatives of Spt7 were constructed containing amino acids 581–1332 (Spt7_581–1332), 873–1332 (Spt7_873–1332) and 1038–1332 (Spt7_1038–1332). Note that each molecule is N-terminally TAP and Flag tagged to allow purification then detection of processed fragments. The position of the histone fold is shown with a black box and the approximate position of the Spt7_SLIK and Spt7_Form3 processing sites by arrows. B. YCpDed-TAP-Flag- Spt7_581–1332, Spt7_873–1332 and Spt7_1038–1332 were expressed in BY3218 (spt7Δ0), tandem affinity purified and Spt7 forms detected by Western blotting with anti-Flag antibody after electrophoresis on an 8–15% gradient gel. Mobility of protein standards with the indicated molecular masses (kDa) is indicated on the left. Arrows on the right marked with 581, 873 and 1038 represent the mobility of truncated TAP-Flag- Spt7_581–1332, Spt7_873–1332 and Spt7_1038–1332, respectively. * marks an additional cleavage product seen with Spt7_581–1332.