Fig. 3.

Transfer of ¹⁴C from starch to TAG during N deprivation. Dunaliella tertiolecta was cultured in N-deprived medium for 14 d. During the first 24 h, cells were labeled with [¹⁴C]bicarbonate. Then cells were washed twice and the medium was replaced by a fresh –N medium containing 50 mM bicarbonate. Each day samples of cells were extracted and fractionated to determine the ¹⁴C level in starch, polar lipids, TAG, and in the water-soluble fraction, as described in the Materials and methods. (A) Changes in ¹⁴C levels in starch and in the water-soluble fraction. (B) Changes in ¹⁴C levels in the starch plus the water-soluble fraction, in the total lipid fraction, and in TAG. Results are expressed in nmol C 10⁶ cells⁻¹ (means ± SD of three independent experiments). (This figure is available in colour at JXB online.)