Abstract
During the fertilization of flowering plants, the pollen tube grows directionally inside the pistil and delivers two non-motile male gametes to the embryo sac. Because the embryo sac is generally encased the ovule, it has being difficult to observe, little is known about the molecular mechanism of angiosperm fertilization for more than 140 years. This pollen tube guidance has been thought to be mediated by chemoattractants derived from target ovule. Previously we showed that in Torenia fournieri, pollen tube attractants are secreted from the synergid cells. Using this in vitro pollen tube guidance assay, a molecule, which induced pollen tube competence to respond to the attractant was uncovered and named AMOR (activation molecule for response capability). AMOR was found to be secreted from ovule, heat-stable, and was collected in a fraction of arabinogalactan proteins. But the nature of AMOR remains unknown.
Here, we report that we established the strategies to purify sufficient amount of AMOR from column purification and found that AGPs from vegetative tissues of other plant species and some Torenia organs also have some AMOR-like activity.
