A subset of FG-nucleoporins is necessary for efficient Msn5-mediated nuclear protein export

► A novel approach to study nuclear protein export kinetics is described. ► Cells lacking the nucleoporins Nup100 or Nup2 exhibit slowed export. ► GLFG repeats of Nup100 are necessary for efficient protein export. ► FXFG repeats in Nsp1 but not Nup1 affect nuclear export kinetics. ► Nup mutations that affect export alter Crz1 transcription factor activity.