Fig. 2. Arl1p is required for the surface targeting of GFP-GPI (Gas1p). (A) The location of GFP-GPI (Gas1p) and Gap1^K9K16-GFP in arl1-, gcs1- and arl3-mutant cells. GFP-GPI (Gas1p) or Gap1^K9K16-GFP was transformed into wild-type (WT), and arl1-, gcs1- and arl3-null cells and then induced in selection medium containing 2% galactose for 16 hours. GFP signals were observed as in Fig. 1A. (B) Distribution of GPI-anchored proteins. Crh1-GFP, Crh2-GFP, Cwp1-GFP or mRFP-Gas1 was transformed into wild-type and arl1-mutant cells. Transformants were grown overnight in selection medium and then transferred to fresh medium. After 3 hours of incubation, GFP signals were observed. (C) The intracellular accumulated mRFP-Gas1 in arl1 mutant cell colocalizes with GFP-Sft2. Plasmids expressing mRFP-Gas1 and GFP-Sft2 were co-transformed into wild-type and arl1-mutant cells. GFP and RFP signals were observed as described in B. Arrows indicate colocalization of mRFP-Gas1 and GFP-Sft2.