Section of Molecular and Cellular Biology, College of Biological Sciences, University of California, Davis, CA 95616, USA. tpowers@ucdavis.edu
Conservation of the rapamycin-sensitive TOR signaling network among eukaryotes has been instrumental to the rapid progress made in this field in recent years. A recent report in Molecular Cell (Urban et al., 2007) now extends this conservation to include Sch9, an AGC protein kinase family member from S. cerevisiae, which appears to be the long sought after yeast ortholog of mammalian S6 kinase 1 (S6K1) and a direct target for the rapamycin-sensitive TOR complex I.