IME4 is a component of a signalling system that couples the MAT genotype and nutritional status to sporulation-specific gene expression. IME4 is normally required for IME1 expression: ime4:TRP1 mutant strains do not express IME1 and the cells arrest with 2c DNA content. When rme1:LEU2 or RES1-1 mutations are also present, IME1 expression is fully restored but the cells still do not sporulate. The observation that IME4 is the same gene as SPO8 (I. Yamashita, pers. comm.) prompted us to examine the arrest phenotype of these doubly mutant strains in more detail: spo8/DSM1 mutants undergo premeiotic DNA synthesis and commitment to intragenic recombination but not spore formation (S. Esposito and S. Klapholz, CSH monograph). We observe that ime4:TRP1 rme1:LEU2 cells arrest prior to the MI division, but with 4c DNA content. Mid/late gene expression (e.g, SPR3, SPR1, SGA1) does not occur. Thus, IME4 is required for the MI transition, independently of its role in promoting IME1 gene expression. It will be important to establish whether the arrest is SPO11-dependent and to examine the cytology of the arrested cells. Thus, it is likely that IME4 transmits nutritional signals at late, as well as early, stages in the meiotic pathway.