Infection structures

Macko V (1981) Inhibitors and stimulants of spore germination and infection structure formation in fungi. In Turian G, Holh HR (eds) The fungal spore morphogenetic controls. Academic Press, New York, p 565... 

Macek, K.J., M.A. Lindberg, S. Sauter, K.S. Buxton, and P.A. Costa. 1976. Toxicity of Four Pesticides to Water Fleas and Fathead Minnows. U.S. Environ. Protection Agen. Rep EPA-600/3-76-099. 57 pp. Macko, V., J.A.A. Renwick, and J.F. Rissler. 1978. Acrolein induces differentiation of infection structures in the wheat stem rust fungus. Science 199 442-443. 

Haustorial mother cells are thought to arise only when the infection hyphae make contact with host cells however, haustorial mother cells do develop occasionally in the absence of the host (15). All of the infection structures prior to the haustorial mother cells develop as a result of the original contact by the germling with the stomate. 

Chemicals can also induce infection structures, and each fungus seems to have its own requirement. For example, Puccinia graminis tritici responds to acrolein (16), while U. appendiculatus responds to K+ (17). The thigmotropic response by U. appendiculatus to the stomate, however, is entirely physical as demonstrated by Wynn (8). 

Figure 2. Infection structures developed by uredospore germlings of U. appendiculatus. (A) Diagram of the infection...

Time-scale of Response. A list of some of the events which occur during the development of infection structures, and the estimated times when the response occurs after contact with the inductive... 

Protein Synthesis and Gene Expression. Development of the infection structures is accompanied by the synthesis of at least 15 differentiation-related (dr) proteins, i.e. proteins not present in the germling until differentiation is induced Fig. 4 (22. A downshift in the synthesis of some proteins also occurs during infection structure development. 

All of the clones isolated so far hybridize with transcripts which appear in germlings at the time when the vesicles form, although the class VI clone also hybridizes with a transcript which appears during development of the appressorium. Thus, the ds-genes appear to have a role in construction of the infection structures. A more precise timing of expression will have to await additional studies. 

Figure35 Model representations of sialic-acid-conjugated polymeric inhibitor subunits used to inhibit viral infection. Structures are not drawn to scale. (Courtesy of Bioconjugate Chem. 1999, (10)2, 273. Copyright 1999 American Chemical Society.)...

Spore Adhesion, Infection Structures and the Infection Process... 

Mendgen, K. and Deising, H. (1993) Tansley Review No. 48. Infection structures of fungal plant pathogens—a cytological and physiological evaluation. New. Phytol., 124,193-213. 

Mendgen, K., A. Schneider, M. Sterk W. Fink. 1988. The differentiation of infection structures as a result of recognition events between some biotrophic parasites and their hosts. J. PhytopathoL 123 259-272. 

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