Transcriptional regulation of meiosis in budding yeast

Table 1. List of positive and negative regulators of transcription of meiosis-specific genes.
Name Brief description of function
ABF1 An essential DNA-binding protein required for DNA replication and the transcription of several
meiosis-specific genes carrying its binding site (UASH).
AMA1 A meiosis-specific subunit of APC/C that is required for degradation of CLB1 in the meiotic cycle.
Required for the transcription of LMG.
BCY1 The regulatory subunit of PKA. Positive regulator for IME1 transcription and sporulation.
CDC25 Ras GDP/GTP exchange factor. Positive activator of PKA, negative regulator of IME1
transcription. Transmits the nitrogen signal to UCS1 and the glucose signal to IREu elements in
IME1 promoter.
CDC28 Cyclin dependent kinase that regulates initiation and progression in the mitotic cell cycle. In a
complex with Cln phosphorylates Ime1 and sequesters it out of the nuclei. Required to activate
Ime2 at the time cells enter the meiotic division.
CDC35 Adenylate cyclase. Positive activator of PKA, negative regulator of IME1 transcription and
sporulation
GCN5 Histone acetylase required for the transcription of EMG.
GPA2 A Gα protein that associates, when GTP bound, with Ime2. An inhibitor of Ime2 kinase activity.
HST1 Histone deacetylase. Represses the transcription of MMG following recruitment by Sum1.
IDS2 A positive regulator of Ime2 activity.
IME1 The master regulator gene of meiosis. A transcriptional activator; recruited by Ume6 to the URS1
element in EMG, and is required for their transcription. The transcription of IME1 depends on the
presence of Mata1 and Matα2 as well as on glucose and nitrogen depletion. Translation and
activity of Ime1 are regulated by nutrients.
IME2 An early meiosis-specific gene encoding serine/threonine kinase, homologous to the human CDK2.
Required for timely and high level transcription of EMG, and for the transcription of MMG and
LMG. Negative regulator of Ime1 stability.
IME4 A positive transcriptional regulator of IME1 whose transcription depends on the presence of Mata1
and Matα2 and nitrogen depletion.
ISW2 In a complex with Itc1 functions as an ATP dependent chromatin-remodeling factor. Required for
the repression of EMG under vegetative growth conditions. Physically associate with Ume6 that
recruits it to URS1 elements.
ITC1 In a complex with Isw2 functions as an ATP dependent chromatin-remodeling factor. Required for
the repression of EMG under vegetative growth conditions.
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