Fig. 6.

Shortening the WOPR linker affects white-to-opaque switching and transcriptional activation. (A) Frequency of white-to-opaque switching for strains with different Wor1 ectopic overexpression constructs. Full-length Wor1 (under control of an inducible pMET3 promoter) converts 100% of white cells to opaque cells under conditions that activate the pMET3 promoter. Replacing full-length Wor1 with a version missing a portion of the linker results in only partial conversion, as shown by both the small number of purely opaque colonies observed and the intermediate appearance of many colonies, which are mixtures of white and opaque cells. (B) Light microscope images of cells in the experiment in A. The Wor1 construct with the shortened linker produces a range of intermediate colony types, with some made up primarily of white cells (row 3, Center) and some with mixtures of white and opaque cells (row 3, Right). (C) Activation of test promoters controlled by full-length Wor1 and two versions of Wor1 missing part of the linker.