ISSN:
1432-2048
Keywords:
Ectomycorrhiza
;
Eucalyptus
;
Pisolithus
;
Symbiosis-related polypeptides
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Changes in protein biosynthesis were examined during the early stages of differentiation of Eucalyptus grandis-Pisolithus tinctorius ectomycorrhizas by two-dimensional polyacrylamide gel electrophoresis of 35S-labelled proteins. Three distinct isolates of P. tinctorius Coker & Couch were chosen based on the rate of ectomycorrhizal formation (i.e. infectivity) with E. grandis W. Hill ex Maiden. The isolate H506 was not able to induce mycorrhiza, isolate 441 showed moderate infectivity and isolate H2144 exhibited a very high infectivity. Mycorrhiza were produced in vitro in a system where seeds were germinated in the presence of fungal mycelium and exudates. The non-mycorrhizal isolate caused no changes in root protein biosynthesis as analyzed by two-dimensional polyacrylamide gel electrophoresis, whereas drastic alterations in protein biosynthesis were observed from initial contact with the aggressive mycobionts. During mycorrhizal development, there was a marked inhibition of plant polypeptides synthesis, enhanced accumulation of some fungal polypeptides and the emergence of symbiosis-specific polypeptides, the so-called ectomycorrhizins. The major changes were observed in a group of fungal acidic polypeptides (apparent molecular weight 28–32 kDa) including the ectomycorrhizin E32. These polypeptides first appeared at contact and their synthesis increased during mycorrhizal formation, suggesting a role in mycorrhizal development, most likely as structural proteins. Up-regulation of the synthesis of fungal symbiosis-related polypeptides was tightly correlated to the infectivity of the strain.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00202599
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