Record ID No. |
1852 |
Author(s) |
Kuga Y., Saito K., Nayuki K., Peterson R.L., Saito M , 2008 |
Affiliation |
Shinshu University, Fac Agr, Dept Food Product Sci, Nagano 3994598, JAPAN |
Title |
Ultrastructure of rapidly frozen and freeze-substituted germ tubes of an arbuscular mycorrhizal fungus and localization of polyphosphate |
Source. Vol.(no):Page |
New Phytologist.178(1):189-200p. |
Categories |
Arbuscular Mycorrhiza |
Subjects |
Biochemistry |
Sub-subjects |
Miscellaneous |
Organism |
n.a. |
Country |
JAPAN, Asia |
Abstracts |
In arbuscular mycorrhizas (AM), the supply of phosphorus from the fungi is one of
the most important benefits to the host plant. Here we describe for the first time the
ultrastructure and polyphosphate (poly P) distribution in rapidly frozen and freeze-substituted
germ tubes of the AM fungus Gigaspora margarita. At the ultrastructural level, phosphorus
distribution was analysed using energy-filtering transmission electron microscopy, and poly P was
detected using an enzyme-affinity method. Semithin sections and live cells were also stained with
4',6-diamidino-2-phenylindole, which is not specific but fluoresces yellow when viewed under UV
irradiation by binding with poly P. The cryotechnique method showed that extensive elongate
ellipsoid vacuoles containing a uniform electron-opaque material occupied most of the cell
volume. Combining the results of multiple methods revealed that poly P was localized in a
dispersed form in vacuoles and in the outer fungal cell wall. These results show the significant
potential of AM fungi for phosphorus storage based on its localization in the extensive
complement of vacuoles in thick hyphae. The mechanism of translocation of poly P in tubular
vacuoles, and the role of poly P in the cell wall, need to be elucidated. |