Figure 2

GERV formation and stability as a function of GTP concentration. (a) GERV formation. Number of GERVs for each diameter range were counted per area of coverslip. GERVs larger than 2 µm in diameter and with at least one third of their perimeter free of aggregates were considered adequate for further experiments and considered. Diameters were measured in micrometers and rounded to integers for classification. Incidence values are averages from four independent preparations of GERVs. From each of the four preparations, aliquots were taken and subjected to nucleotide concentrations between 0 to 50 mM GTP. In three out of the four microsome preparations, the 5 mM GTP condition yielded the largest density of GERVs. In one out of the four preparations, 10 mM GTP was most successful. (b) GERV stability. The number and size distribution of the GERVs were evaluated without apyrase (0 h) and 0.5 h, 2 h, and 4 h after addition of 0.01 U ml⁻¹ apyrase. Quantification criteria were applied as described for (a). Values are averages from two apyrase assays.