Figure 5.—
Rapamycin confers canavanine and thialysine resistance, while deletion of tor1+ confers hypersensitivity to these toxic amino acid analogs. (A) Serial dilutions of exponentially growing wild-type (TA001), Δtsc2 (TA450), or Δfkh1 (TA597) cells were spotted on EMM medium containing canavanine or thialysine in the absence or presence of rapamycin. (B) Serial dilutions of TA001, TA450, TA390, TA568, TA561, and TA459 were spotted on EMM plates in the presence of either canavanine or thialysine. (C) Working model. Tor2 positively regulates growth, allowing the G1/S transition under conditions of sufficient nutrients. Tor2 lies downstream of Rhb1 and is negatively regulated by Tsc1–2, while Tor1 acts in parallel with the Tsc1/2–Rhb1 module. The functions that are inhibited by rapamycin (R) are indicated in italics.