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Fig. 4. PtdIns(4,5)P2 synthesis at fertilization is
Ca2+-dependent. (A) Changes in [Ca2+]i and
PH-GFP distribution recorded at fertilization in an egg pretreated with 1
µM BAPTA-AM. Similar results were obtained in 15 eggs. (B) Upper panel,
changes in [Ca2+]i and PH-GFP distribution elicited by
uncaging Ins(1,4,5)P3 using a low UV power (0.5%
excitation-indicated by the horizontal bar). Similar results were obtained in
eight eggs. Lower panel, changes in [Ca2+]i and PH-GFP
distribution elicited by uncaging Ins(1,4,5)P3 using a
tenfold higher UV power (5% excitation-indicated by the horizontal bar).
Similar results were obtained in five eggs. For abbreviations, see
Fig. 2 legend.