Fig. 3. Washing of yolk granules in the chaotropic salt, KI, inhibits tethering. (A) Granules washed three times post-isolation in IM buffer. (B) Granules washed three times post-isolation in KI buffer. Tethering is no longer evident. (C) Comparison of KI-washed and control, IM-washed granule tethering responses using a novel, rapid, semi-quantitative assay. Granule samples in 96-well plates are centrifuged to pellet the large tethered aggregates. Granules not tethered, which remain suspended in buffer in the upper half of the contents of each well, are then transferred to a fresh well and the absorbance of this transferred measured. Tethering efficiency is an inverse function of measured absorbance. Hence the absorbance of the KI-washed granules (not tethered, see panel B) is higher than that of IM-washed granules (tethered, see panel A). Error bars indicate s.d. (n=6). Bar, 10 µm.