FIG. 5.
β1,6-Glucan colocalizes with plasma membrane-derived vesicles. To induce accumulation of post-Golgi secretory vesicles, sec1-1 cells were kept at the restrictive temperature for 2 h. The cells were spheroplasted and gently lysed. The resulting homogenate was fractionated by differential centrifugation, and the microsomal fraction was separated by gel filtration on a Sephacryl S-1000 column (55, 56). Aliquots of each column fraction (x axis) were assayed for protein content, invertase, plasma membrane ATPase, and β1,6-glucan content. y axes represent, from top to bottom, protein (micrograms), invertase (micromoles of Glc per minute), plasma membrane ATPase (micromoles of Pi per minute), and β1,6-glucan (arbitrary densitometric units).