Kassir Y, Granot D, Simchen G
Department of Genetics, Hebrew University, Jerusalem, Israel.
Cell. 1988 Mar 25;52(6):853-62. doi: 10.1016/0092-8674(88)90427-8.
IME1 (Inducer of MEiosis) was cloned due to its high copy number effect: it enabled MAT insufficient strains to undergo meiosis. Disruption of IME1 results in a recessive Spo- phenotype. Diploids homozygous for the two mutations ime1-0, rme1-1 are also meiosis deficient. We conclude that IME1 is a positive regulator of meiosis that normally is repressed by RME1. RME1 is repressed by a complex of MATa1 and MAT alpha 2 gene products. IME1 is also regulated by the environment: no transcripts could be detected in glucose growing cells, in contrast to acetate growing cells. Starvation for nitrogen further induced (6- to 8-fold) transcription of IME1, but, as expected, the induction was found only in MATa/MAT alpha or rme1-1/rme1-1 diploids. Furthermore, the IME1 multicopy plasmids promoted sporulation in rich media.
减数分裂诱导因子1（IME1）因其高拷贝数效应而被克隆：它使MAT功能缺陷型菌株能够进行减数分裂。IME1的破坏会导致隐性孢子形成缺陷表型。对于ime1 - 0、rme1 - 1这两个突变纯合的二倍体也存在减数分裂缺陷。我们得出结论，IME1是减数分裂的正向调节因子，通常受到RME1的抑制。RME1受到MATa1和MATα2基因产物复合物的抑制。IME1也受环境调节：与在乙酸盐培养基中生长的细胞相比，在葡萄糖培养基中生长的细胞中检测不到转录本。氮饥饿进一步诱导（6至8倍）IME1的转录，但正如预期的那样，仅在MATa/MATα或rme1 - 1/rme1 - 1二倍体中发现这种诱导现象。此外，IME1多拷贝质粒在丰富培养基中促进孢子形成。
