The impact of melaphene on the expression of chloroplastic chaperone protein HSP70B and photosynthetic pigments in cells of <Emphasis Type="Italic">Chlamydomonas reinhardtii</Emphasis>

The effects of growth regulator of the new generation—melamine salt of bis(oxymethyl)phosphine acid (melaphene)—on culture growth, pigment and protein content, and the induction of protective chloroplastic chaperone HSP70B in Chlamydomonas reinhardtii CW15 cells were studied. Melaphene exhibited 10–30% growth inhibition at 10⁻⁹–10⁻²% concentration. At 10⁻⁹–10⁻⁴% of melaphene electrophoretic concentration, the pattern of cellular proteins was similar to the control. The alterations in protein content of algae cells were detected only at 10⁻²% concentration. The content of chlorophyll and carotenoids in melaphene-treated cells was 17–40% lower than in the control. Melaphene at 10⁻⁹–10⁻²% concentration inhibited HSP70B induction by 39–43% compared to untreated cells. The potential mechanism of melaphene effect might involve its influence on nuclear gene expression.