DNA ENDOREDUPLICATION, RNA AND PROTEIN-SYNTHESIS DURING GROWTH AND DEVELOPMENT OF THE ANTHERIDIAL BASAL-CELL IN CHARA-VULGARIS L

Cytophotometric measurements of nuclear DNA contents and morphometric analyses indicate that the level of endopolyploidy plays an important role in determining the maximum size, transcriptional and translational activity that the antheridial basal cell attains during successive stages of spermatogenesis in Chara a vulgaris. During the proliferative period of antheridial development, the metabolic activity of basal cell, expressed as the total incorporation of radioactive uridine and leucine was found to increase gradually with the increasing DNA C-values, yet both the synthesis of RNA and then the synthesis of proteins become reduced at the stage preceding spermiogenesis. In accordance with some earlier data [2], the obtained results seem to support the hypothesis that regulatory mechanisms of symplasmic connections between the antheridium and a thallus participate in the regulation of morphogenesis of the male sex organs in Chara.