Format

Send to

Choose Destination
Curr Biol. 2012 Jun 19;22(12):1090-4. doi: 10.1016/j.cub.2012.04.041. Epub 2012 May 17.

Gamete fusion is required to block multiple pollen tubes from entering an Arabidopsis ovule.

Author information

1
Department of Molecular Biology, Cell Biology, and Biochemistry, 185 Meeting Street, Brown University, Providence, RI 02912, USA.

Abstract

In double fertilization, a reproductive system unique to flowering plants, two immotile sperm are delivered to an ovule by a pollen tube. One sperm fuses with the egg to generate a zygote, the other with the central cell to produce endosperm. A mechanism preventing multiple pollen tubes from entering an ovule would ensure that only two sperm are delivered to female gametes. We use live-cell imaging and a novel mixed-pollination assay that can detect multiple pollen tubes and multiple sets of sperm within a single ovule to show that Arabidopsis efficiently prevents multiple pollen tubes from entering an ovule. However, when gamete-fusion defective hap2(gcs1) or duo1 sperm are delivered to ovules, as many as three additional pollen tubes are attracted. When gamete fusion fails, one of two pollen tube-attracting synergid cells persists, enabling the ovule to attract more pollen tubes for successful fertilization. This mechanism prevents the delivery of more than one pair of sperm to an ovule, provides a means of salvaging fertilization in ovules that have received defective sperm, and ensures maximum reproductive success by distributing pollen tubes to all ovules.

PMID:
22608506
PMCID:
PMC3973743
DOI:
10.1016/j.cub.2012.04.041
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center