Fig. 1. Early sec mutants block cycling of Atg9. The structure of the peripheral ER and the mitochondrial reticulum is altered in the sec12 mutant at nonpermissive temperatures. (A,B) The wild-type (SEY6210) and sec12 (FBY217) strains both transformed with the plasmid expressing Spo7-GFP (YEplac122-TRP1-SPO7-GFP) were grown at 24°C (A) and then transferred to 37°C (B) for 2 hours. Cells were labeled with MitoFluor Red and viewed before and after the temperature shift. Images of the fluorescent signal were acquired while focusing on either the center or the periphery of the cells. DIC, differential-interference-contrast images.