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Published on: August 15, 2017
Integrin-like proteins in the pollen tube: detection, localization and function
1Institute of Molecular Cell Biology, Hebei Normal University, Shijiazhuang, People s Republic of China.
Plant & Cell Physiology
|January 10, 2001
Summary
Integrin-like proteins are present in pollen tubes, potentially aiding growth and style interaction. These proteins, mainly alpha(v) and beta3 subunits, are found near the pollen tube tip and plasma membrane.
Area of Science:
- Plant reproductive biology
- Cellular and molecular biology
Background:
- Integrins are crucial cell adhesion receptors in animals.
- Pollen tube growth is essential for plant fertilization.
Purpose of the Study:
- To investigate the presence and distribution of integrin-like proteins in pollen tubes.
- To determine the potential role of these proteins in pollen tube growth and function.
Main Methods:
- Immunofluorescent labeling and confocal microscopy to visualize protein localization.
- Western blotting to detect protein presence and subunits.
- Functional assays using antibodies and peptides to assess growth inhibition.
Main Results:
- Intense immunostaining of integrin-like proteins observed near the tip and plasma membrane of pollen tubes in Lilium davidii and Nicotiana tabacum.
- Western blotting confirmed the presence of alpha(v), beta3, and vitronectin receptor (VnR)-like proteins in pollen tube plasma membranes.
- While in vitro growth was unaffected, antibody and peptide treatments inhibited pollen tube growth under quasi in vivo conditions.
Conclusions:
- Integrin-like proteins are present in pollen tubes, with alpha(v) and beta3 subunits being prominent in lily pollen.
- These proteins appear to play a role in pollen tube tip growth and interaction with the style's extracellular matrix.
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