Molecular and cellular mechanisms of neutral lipid accumulation in diatom following nitrogen deprivation.
Molecular and cellular mechanisms of neutral lipid accumulation in diatom following nitrogen deprivation.
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DOI：
10.1186/1754-6834-6-67
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发表时间：
2013-05-04
影响因子：
6.3
通讯作者：
Li HY
中科院分区：
文献类型：
--
作者：
Yang ZK;Niu YF;Ma YH;Xue J;Zhang MH;Yang WD;Liu JS;Lu SH;Guan Y;Li HY
氮限制可诱导微藻中性脂质积累，抑制其生长。因此，为了获得高生物量和高脂质含量的培养物，并探讨脂质积累机制，我们对处于指数生长后期的三角褐指藻进行了氮剥夺。中性脂含量增加2.4倍，油体的数量和总体积均显著增加，细胞密度略有上升。RNA-Seq分析结果表明，缺氮胁迫下，1213个基因（包括碳固定、TCA循环、甘油脂代谢和氮同化等关键基因）的表达量增加，假发现率为0.001。然而，大多数捕光复合体基因表达下调，电子显微镜下观察到叶绿体膜广泛降解，光合效率下降。进一步鉴定的脂质类表明，MGDG和DGDG，叶绿体膜的主要脂质成分的水平，显着下降和三酰甘油（TAG）水平显着上升，表明细胞内膜重塑实质上有助于中性脂质积累。我们的研究结果揭示了硅藻中性脂质积累的分子机制和参与脂质代谢的关键基因。它们还提供了改进微藻生物柴油生产的可能战略的指示。
Nitrogen limitation can induce neutral lipid accumulation in microalgae, as well as inhibiting their growth. Therefore, to obtain cultures with both high biomass and high lipid contents, and explore the lipid accumulation mechanisms, we implemented nitrogen deprivation in a model diatom Phaeodactylum tricornutum at late exponential phase. Neutral lipid contents per cell subsequently increased 2.4-fold, both the number and total volume of oil bodies increased markedly, and cell density rose slightly. Transcriptional profile analyzed by RNA-Seq showed that expression levels of 1213 genes (including key carbon fixation, TCA cycle, glycerolipid metabolism and nitrogen assimilation genes) increased, with a false discovery rate cut-off of 0.001, under N deprivation. However, most light harvesting complex genes were down-regulated, extensive degradation of chloroplast membranes was observed under an electron microscope, and photosynthetic efficiency declined. Further identification of lipid classes showed that levels of MGDG and DGDG, the main lipid components of chloroplast membranes, dramatically decreased and triacylglycerol (TAG) levels significantly rose, indicating that intracellular membrane remodeling substantially contributed to the neutral lipid accumulation. Our findings shed light on the molecular mechanisms of neutral lipid accumulation and the key genes involved in lipid metabolism in diatoms. They also provide indications of possible strategies for improving microalgal biodiesel production.
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影响因子：
3.7
作者：
Kroth PG;Chiovitti A;Gruber A;Martin-Jezequel V;Mock T;Parker MS;Stanley MS;Kaplan A;Caron L;Weber T;Maheswari U;Armbrust EV;Bowler C
通讯作者：
Bowler C
影响因子：
2.2
作者：
Chen, Wei;Zhang, Chengwu;Hu, Qiang
通讯作者：
Hu, Qiang
拟南芥冷冻和冷冻后恢复过程中质体外和质体脂质的差异降解
影响因子：
4.8
作者：
Li, Weiqi;Wang, Ruiping;Wang, Xuemin
通讯作者：
Wang, Xuemin
影响因子：
4.2
作者：
Byrne SL;Foito A;Hedley PE;Morris JA;Stewart D;Barth S
通讯作者：
Barth S
影响因子：
7.4
作者：
Miller, Rachel;Wu, Guangxi;Benning, Christoph
通讯作者：
Benning, Christoph