Figure 2.

In vitro localization of AtTim21-like precursor proteins into isolated Arabidopsis mitochondria. Radiolabeled precursor proteins incubated with isolated mitochondria under conditions that support import. Subsequently, mitochondria were treated with PK before or after rupture of the outer membrane via osmotic shock. Lane 1, precursor protein alone, lane 2, precursor protein incubated with mitochondria, lane 3, as lane 2 except with the addition of PK. Lane 4 and 5, as lane 2 and 3 except with the addition of valinomycin prior to import, lane 6–9, as lanes 2–5 except with rupture of the outer membrane following import and prior to PK treatment. The apparent molecular weights of the precursor and mature proteins are indicated on the right. Arrows indicate the mature processed protein. Abbreviations: Mit, mitochondria; Val, valinomycin; Mit^*OM, mitoplasts; PK, Proteinase K.