| Abstract: | This study focuses upon the developmental transition of theparasitic plant Striga hermonthica from its freeliving state(germinated seedling) to its parasitic state after developmentof an infection organ: the haustorium. A new method has beendeveloped that allows the production of gram quantities of germinatedand haustorially-induced Striga seedlings, thereby facilitatingbiochemical and molecular analysis of haustorial induction.Water-soluble proteins have been extracted from germinated seeds(stage A) and seedlings treated with 2,6-dimethoxy-p-benzoquinone(2,6-DMBQ) to induce haustorium (stage B). Samples were analysedby two-dimensional polyacrylamide gel electrophoresis and quantitativeas well as qualitative differences could be observed. In particulara group of four highly abundant acidic proteins (molecular weight39 kDa, pl 5.1, 5.3, 5.3, 5.6) and three other proteins (molecularweight 12 kDa, pl 6.9; 17 kDa, pl 4.4; 17 kDa, pl 4.45) wereseen in stage A while at least four proteins (molecular weight21.5 kDa, pl 6.4; 21.5 kDa, pl 6.3; 31 kDa, pl 5.1; 34 kDa,pl 6.2) were present in greater abundance in stage B. In orderto compare watersoluble protein with newly synthesized proteinpatterns, mRNAs from the two stages of development were isolatedand cell-free translation products analysed by 2-D PAGE. Two-Dgels of cell-free translation products showed the appearanceof six proteins in stage B (molecular weight ranging from 10to 35 kDa) and the presence of three acidic proteins in stageA with one protein (molecular weight 40 kDa) very similar insize to the triplet of proteins in the water-soluble protein2-D gels. Key words: Striga hermonthica (Del.) Benth., haustorium, 2-D PAGE, 2,6-DMBQ, translation in vitro |
