Adhesion and cell movement during pollination: cherchez la femme

Pollination involves an interaction between the female tissues (stigma, sty le and ovary) and the male gametophyte or the pollen tube cell, which conta ins the sperm cells. Freezing methods now allow us to visualize the extrace llular matrices that guide pollen tubes to the ovary, Adhesion of the polle n tube to these specialized extracellular matrices might be a mechanism of guidance and tube cell movement in the style. In lily, the stylar adhesion molecules are a pectin and a small, basic cysteine-rich protein, both of wh ich are necessary to induce tube cell adhesion to an artificial, in vitro s tyle matrix.