FIG. 3.

Disruption of WdCDC42 by replacement with a SUR selection marker. (A) Strategy for disruption of WdCDC42 with a 5-kb linear DNA fragment containing SUR and partial WdCDC42 sequences. Homologous recombination resulted in the replacement of a 21-bp portion of the WdCDC42 coding sequence (codons 76 to 83) with the 3-kb SUR marker. (B) Southern analysis of wdcdc42 disruption transformants. DNA samples were digested by SacII or ClaI, and the blot was hybridized with a WdCDC42 probe. The fragments of wild-type (wt) WdCDC42 were expected to be 5 kb when cut by SacII and 4.5 kb when cut by ClaI, whereas a fragment containing a SUR insertion would be 8 kb when cut by SacII and would produce two bands of 7 and 0.5 kb when cut by ClaI because of an introduced ClaI restriction site at SUR. Note that Ad42-41, -58, and -59 and Bd42-60 and -53 showed the expected patterns of band shifts and therefore were specific disruption transformants.