A substantial portion of the ribulose 1,5-diphosphate carboxylase activity in the endosperm of germinating castor beans (Ricinus communis var. Hale) is recovered in the proplastid fraction. The partially purified enzyme shows homology with the enzyme from spinach (Spinacia oleracea) leaves, as evidenced by its reaction against antibodies to the native spinach enzyme and to its catalytic subunit...

Wilt, caused by Fusarium oxysporum f. sp. ricini, is the most severe disease of castor bean (Ricinus communis). For the development of marker for wilt-resistant gene, 200 F2 individuals from a cross between the resistant cultivar 48-1 and the susceptible cultivar VP-1 were inoculated with a race of Fusarium oxysporum f. sp. ricini. Bulked segregant analysis was used to search for random amplifi...

A detailed knowledge of storage reserve accumulation in developing seeds can provide vital information to create strategies for improving the lipid content as well as the natural value of castor (Ricinus communis L.) crop. After hand pollination (female flowers-tagged), seed filling (lipid and protein accumulation) in castor bean is initiated as early as 7 days after pollination (DAP). Accumula...

Glyoxysomes of endosperm tissue of castor bean (Ricinus communis L.) seedlings were solubilized in a detergent and added to a lipid bilayer. Conductivity measurements revealed that the glyoxysomal preparation contained a porin-like channel. Using an electrophysiological method, which we established for semiquantitative determination of porin activity, we were able to demonstrate that glyoxysoma...

The distribution of polysomes in the cells of the endosperm of very young (48 hours of germination) seedlings of castor bean (Ricinus communis var. Hale) has been examined. Seedlings exposed to 100 micromolar gibberellin A(3) for periods up to 24 hours showed increased numbers of polysomes associated with endomembranes. Cytosol-derived polysomes were generally of a shorter mean length than memb...

The intrinsic membrane proteins of the endoplasmic reticulum from endosperm of maturing and germinated seedlings of castor bean (Ricinus communis) were studied. Preparations were simultaneously subjected to two-dimensional polyacrylamide gel electrophoresis. At least 30 separate proteins were distinguished by staining the gels with Coomassie R-250. The characteristic protein profiles obtained f...

A technique for the isolation of intact plastids from spinach (Spinacia oleracea) and pea (Pisum sativum) leaves, pea roots and castor bean (Ricinus communis) endosperm is described. This technique involves brief centrifugation of whole homogenates on density gradients. Intact plastids were located in the gradient by assaying for triose phosphate isomerase activity. Contamination of the plastic...