ANALYSIS OF DIFFERENTIATION AND DEVELOPMENT OF THE SPECIALIZED INFECTION STRUCTURES FORMED BY BIOTROPHIC FUNGAL GIANT PATHOGENS USING MONOCLONAL-ANTIBODIES

Monoclonal antibodies have been used to study the differentiation and development of the specialized infection structures formed in the Coll etotrichum-bean and powdery mildew - pea interactions. In the Colletot richum lindemuthianum - bean interaction, monoclonal antibodies have b een used to show that the extracellular matrices associated with conid ia, germ tubes, and appressoria differ in composition and that the ext racellular glycoproteins are organized into specific regions of the fu ngal cell surface. Monoclonal antibody UB27 has been used to show that the plasma membrane of appressoria is differentiated into distinct do mains, with the integral membrane glycoprotein identified by UB27 bein g excluded from the pore region. UB25 recognizes a glycoprotein locate d specifically in the cell wall/matrix of intracellular hyphae and is expressed only during the biotrophic phase of development. In the Erys iphe pisi - pea interaction, UB8 and UB10 identify glycoproteins speci fic to the haustorial plasma membrane within the haustorial complex. M onoclonal antibodies that recognize the extrahaustorial membrane have shown that this membrane contains specific components, as well as glyc oproteins in common with the host plasma membrane. UB8 has been succes sfully used to isolate a gene sequence coding for the protein antigen, by immunoscreening a cDNA expression library prepared from infected e pidermis. An antibody that recognizes the plant endoplasmic reticulum has been used to show that this structure reorganizes around the devel oping haustorial complex in pea epidermal cells.