Fig. 1.

Schematic outline of the strategy used for isolation of a- and α-type yeast cells. a Plasmid map of pLhyS-2 K-Pa1, which was used for the isolation of a-type yeast cells. b Isolation of a-type yeast cells using G418 selection. Formation of the a1-α2 complex in α-type and a/α-type cells represses expression of the kanMX4 marker gene. Only a-type cells are able to survive in culture medium containing G418 by expressing the kanMX4 marker gene. c Plasmid map of pHhyS-3 K-2α, which was used for the isolation of α-type yeast cells. d When introduced into a-type and a/α-type cells, the α2 protein represses expression of the kanMX4 marker gene. Only α-type cells are able to survive in culture medium containing G418 by expressing the kanMX4 marker gene