THE PLANT CELL, Vol 3, Issue 6 629-635, Copyright © 1991 by American Society of Plant Biologists
A Homolog of the Substrate Adhesion Molecule Vitronectin Occurs in Four Species of Flowering Plants
L. C. Sanders, C. S. Wang, L. L. Walling and E. M. Lord
Department of Botany and Plant Sciences, University of California, Riverside, California 92521
The extracellular matrix (ECM) has been implicated in the primary
developmental processes of many organisms. A family of secretory adhesive
glycoproteins called substrate adhesion molecules (SAMs) is believed to
confer these dynamic capabilities to the ECM in animals. In this paper, we
report the existence of SAM-like genes and gene products in flowering
plants. Hybridizations with a human vitronectin cDNA probe and genomic DNA
from broad bean, soybean, and tomato revealed vitronectin-like sequences.
Human vitronectin antibodies cross-react with a 55-kilodalton protein in
leaf and root protein extracts from lily, broad bean, soybean, and tomato.
In addition, immunocytochemical staining of frozen sections of lily leaf
and broad bean gynoecium demonstrated that vitronectin-like proteins were
localized to the ECM on the cell surface, with the most intense labeling
residing in the transmitting tract of broad bean gynoecium.
