Granot D, Margolskee J P, Simchen G
Department of Genetics, Hebrew University, Jerusalem, Israel.
Mol Gen Genet. 1989 Aug;218(2):308-14. doi: 10.1007/BF00331283.
Meiosis and sporulation in yeast are subject to two types of regulation. The first depends on environmental conditions. The second depends on a genetic pathway which involves the control of the positive regulatory gene IME1 by RME1, which is in turn controlled by the MAT locus. The presence of IME1 on a multicopy plasmid enables cells to undergo meiosis regardless of their genotype at MAT or RME1. We show here that a multicopy plasmid carrying IME1 also enables meiosis, regardless of the environment. Therefore, both kinds of regulation appear to act through IME1. Furthermore, the behavior of multicopy plasmids carrying various segments from the IME1 region suggests that the region upstream of IME1 contains both positive and negative regulatory sites. Control of IME1 by the environment and by the MAT pathway both act through negative regulatory sites.
酵母中的减数分裂和孢子形成受到两种类型的调控。第一种取决于环境条件。第二种取决于一条遗传途径，该途径涉及RME1对正向调控基因IME1的控制，而RME1又受MAT基因座的控制。多拷贝质粒上存在IME1可使细胞进行减数分裂，而不论其在MAT或RME1处的基因型如何。我们在此表明，携带IME1的多拷贝质粒也能使细胞进行减数分裂，而不论环境如何。因此，这两种调控似乎都是通过IME1起作用的。此外，携带IME1区域不同片段的多拷贝质粒的行为表明，IME1上游区域同时包含正向和负向调控位点。环境和MAT途径对IME1的控制均通过负向调控位点起作用。
