LAMMER Kinase Lkh1 Is an Upstream Regulator of Prk1-Mediated Non-Sexual Flocculation in Fission Yeast

The cation-dependent galactose-specific flocculation activity of the Schizosaccharomyces pombe null mutant of lkh1⁺, the gene encoding LAMMER kinase homolog, has previously been reported by our group. Here, we show that disruption of prk1⁺, another flocculation associated regulatory kinase encoding gene, also resulted in cation-dependent galactose-specific flocculation. Deletion of prk1 increased the flocculation phenotype of the lkh1⁺ null mutant and its overexpression reversed the flocculation of cells caused by lkh1 deletion. Transcript levels of prk1⁺ were also decreased by lkh1⁺ deletion. Cumulatively, these results indicate that Lkh1 is one of the negative regulators acting upstream of Prk1, regulating non-sexual flocculation in fission yeast.

Role of LAMMER Kinase in Cell Wall Biogenesis during Vegetative Growth of Aspergillus nidulans

Depending on the acquisition of developmental competence, the expression of genes for beta-1,3-glucan synthase and chitin synthase was affected in different ways by Aspergillus nidulans LAMMER kinase. LAMMER kinase deletion, DeltalkhA, led to decrease in beta-1,3-glucan, but increase in chitin content. The DeltalkhA strain was also resistant to nikkomycin Z.