Systematic analysis of < i > tup1 < /i > and < i > cyc8 < /i > mutants reveals distinct roles for < i > TUP1 < /i > and < i > CYC8 < /i > and offers new insight into the regulation of gene transcription by the yeast Tup1-Cyc8 complex

We examinedTUP1 andCYC8 single and double deletion mutants and show thatCYC8 represses more genes thanTUP1, and that there are genes subject to (i) unique repression byTUP1 orCYC8, (ii) redundant repression byTUP1 andCYC8, and (iii) there are genes at which de-repression in acyc8 mutant is dependent uponTUP1, and vice-versa. We also reveal that Tup1p and Cyc8p can make distinct contributions to commonly repressed genes most likely via specific interactions with different histone deacetylases. Furthermore, we show that Tup1p and Cyc8p can be found independently of each other to negatively regulate gene transcription and can persist at active genes to negatively regulate on-going transcription. Together, these data suggest that Tup1p and Cyc8p can associate with active and inactive genes to mediate distinct negative and positive regulatory roles when functioning within, and possibly out with the complex.

Source: PLoS Genetics - August 11, 2023 Category: Genetics & Stem Cells Authors: Brenda Lee Source Type: research