Fig. 1

The effect of different cell densities on the relative intracellular Fe content and relative expression of ISIP1 and ISIP2a of P. tricornutum. The cells were adjusted to different cell densities (L for low-cell density, M for middle cell density, and H for high-cell density) and cultured at white light (WL) and dark (Dark) for 24 h. Then, intracellular Fe content with different cell densities was determined under white light (WL, a) or dark conditions (Dark, b) and normalized by WL-L Fe content. The relative expression of ISIP1 and ISIP2a of P. tricornutum with different cell densities were plotted under white light (WL, c) or dark conditions (Dark, d). Data was shown as mean values ± SD for three independent experiments