PiggyBac transposon-mediated mutagenesis and application in yeast Komagataella phaffii

Objective Around one-fourth of the Komagataella phaffii genes encode hypothetical proteins with unknown functions. However, lack of powerful tools for genetic screening in K. phaffii significantly limits the functional analysis of these unknown genes. Transposon mutagenesis has been utilized as an insertional mutagenesis tool in many other organisms and would be extremely valuable if it could be applied in K. phaffii . Results In this study, we investigated in K. phaffii the transposition activity and efficiency of piggyBac ( PB ) transposon, a DNA transposon from the cabbage looper moth Trichoplusia ni through the integrated-plasmid system. We also designed a binary-plasmid system which could generate stable mutants. Finally we evaluated the quality of this mutagenesis system by a simple screening for functional genes involved in K. phaffii carbon catabolite repression. Conclusions Our results demonstrate that PB -mediated mutagenesis could be a feasible and useful tool for functional gene screening in K. phaffii .