Organospecific reactions of yellow lupin seedlings to lead

Abstract

Changes caused by lead, supplied in the form of Pb(NO3)2, in roots and hypocotyls of 4 day old yellow lupin (Lupinus luteus L. cv. ventus) seedlings have been analyzed using a transmission electron microscope and polyacrylamide gel electrophoresis (PAGE). The cells of all examined parts of the roots growing in the presence of Pb²⁺ contained many lead deposits (mainly in the cell walls and vacuoles) and the increased amount of polypeptides of molecular weight close to 16 kDa have been observed. Similar changes were detected in the area of hypocotyl adjoining the root. However, in upper regions of the hypocotyl only a slight amount of lead deposits was visible and the 16 kDa polypeptide content was comparable to the control cells. The obtained results indicate a relationship between the presence of lead deposits in cells and accumulation of polypeptides of - 16 kDa. The results seem also to indicate that in the analyzed parts of the seedlings, both the amount of accumulated polypeptides of MW - 16 kDa and the amount of lead decreased from root tip to hypocotyl.