Calcium (Ca2+) plays essential roles in generative reproduction of angiosperms, but the sites and mechanisms of Ca2+ storage and mobilization during pollen-pistil interactions have not been fully defined. Both external and internal Ca2+ stores are likely important during male gametophyte communication with the sporophytic and gametophytic cells within the pistil. Given that ...
Main conclusion Calreticulin is involved in stabilization of the tip-focused Ca 2+ gradient and the actin cytoskeleton arrangement and function that is required for several key processes driving Petunia pollen tube tip growth. Although the precise mechanism is unclear, stabilization of a tip-focused calcium (Ca2+) gradient seems to be critical for pollen germination and pollen tube ...