Ternary Complex Formation of Ino2p-Ino4p Transcription Factors and Apl2p Adaptin β Subunit in Yeast
Yeast Ino2p-Ino4p heterodimeric complex is well known as a transcriptional activator for the genes regulated by inositol and choline, such as the <I>INO1</I> gene. Apl2p is a large subunit of the yeast adaptin complex, an adaptor complex required for the clathrin coat to bind to the membrane. We found that Ino2p, Ino4p, and Apl2p form a ternary complex. This interaction was initially observed in a yeast two-hybrid study and subsequently verified by co-immunoprecipitation. Ino2p and Ino4p bind to Apl2p in the same region of Apl2p, <I>viz.</I>, at the middle part and the C-terminal part. Ino2p and Ino4p bind to Apl2p independently, but more strongly when both are present. Furthermore, a disruption of <I>APL2</I> together with <I>INO2</I> or <I>INO4</I> rendered yeast cells sensitive to oxidative stress. <I>INO2-APL2</I> double disruptants also showed growth inability in non-fermentable carbon sources, such as glycerol. These results indicate a genetic interaction between <I>APL2</I>, <I>INO2</I> and <I>INO4</I> and uncovere novel functions of the Ino2p-Ino4p-Apl2p complex in yeast.
- Bioscience, biotechnology, and biochemistry
Bioscience, biotechnology, and biochemistry 70(11), 2604-2612, 2006-11-23
Japan Society for Bioscience, Biotechnology, and Agrochemistry