Transcriptional reporters for genes activated by cell wall stress through a non-catalytic mechanism involving Mpk1 and SBF.

The Mpk1 MAP kinase of the cell wall integrity (CWI) signalling pathway induces transcription of the FKS2 gene in response to cell wall stress through a non-catalytic mechanism that involves stable association of Mpk1 with the Swi4 transcription factor. This dimeric complex binds to a Swi4 recognition site in the FKS2 promoter. The Swi6 transcription factor is also required to bind this ternary complex for transcription initiation to ensue. In this context, the Mlp1 pseudokinase serves a redundant function with Mpk1. We have identified three additional genes, CHA1, YLR042c and YKR013w, that are induced by cell wall stress through the same mechanism. We report on the behaviour of several promoter-lacZ reporter plasmids designed to detect cell wall stress transcription through this pathway.