Light effects on DNA and protein synthesis in generative and non-generative cells of the antheridium of Chara vulgaris (Charophyta)

Abstract

Studies of the effects of light on antheridial cells in Chara vulgaris Linnaeus (Charophyta) show that changes in the dynamics of antheridial filament growth are closely correlated with metabolic activity in manubria and capitular cells. Inhibition of DNA synthesis in darkness can be observed in antheridial filaments during mitotic divisions and during endoreplication in capitular cells and manubria. During spermatogenesis, when the number of cells in the antheridial filaments increases, a decrease in sensitivity to the absence of light in all antheridium cells is observed. The least sensitive period to darkness occurs at the time of differentiation of spermatozoids (spermiogenesis). After plants have been transferred from light to darkness and from darkness to light, manubria, capitular cells and antheridial filaments in young antheridia respond by a considerable decrease or increase in translation activity, respectively. However, immediately after changing the light conditions, the strongest response is found in manubria, being weaker in capitular cells and weakest in antheridial filaments.