小鼠肝再生时线粒体嵴形态结构的变化规律及其调控机制对能量供应影响的研究

Liver insufficiency and dysfunction frequently occurs after major liver resection in surgical treatment of liver malignancy. Understanding the mechanisms of liver insufficiency and failure after MLR will facilitate the development of effective therapies. The outcome of liver insufficiency and failure is depend on regeneration of liver cells, while energy is vital to liver cells regeneration. ..Mitochondria are double membrane-bound organelles whose shape is instrumental to their function in diverse cellular processes such as metabolism, energy conversion, and calcium homeostasis. The inner mitochondrial membrane has the highest density of protein in the cell and is differentiated into three distinct interconnected domains: the boundary region, which are flattened membranes that lie in close apposition to the outer membrane; cristae membranes, which are lamellar invaginations with highly curved edges; and cristae junctions, which are relatively narrow tubules that connect cristae to the boundary membrane and may act as a physical partitioning mechanism that prevents and/or regulates the intermixing of proteins between cristae and the boundary domains. Cristae are known to house the respiratory chain complexes, along with cytochrome C and ATP synthase. Energy conversion occurs at the cristae through oxidative phosphorylation of respiratory chain complexes and ATP synthase. We found the relationship between energy conversion and mitochondrial ultrastructure in pilot study. The relationship between respiratory chain complexes and cristae shape remains unclear. This study was to investigate the changes in the expression of Mitofilin、Cox17、F0F1-ATP synthase and the mechanisms how to regulate the whole procedure, adjustment the morphological structure of cristae as a novel therapeutic target for liver insufficiency. Thus new, therapeutics and promote recovery of liver function would advance the field and clinical medicine significantly. .We will use BN-PAGE, Co-IP/mass spectrometry, electron microscope and multiphoton microscopic system to investigate the communication between cristae and the stability of respiratory chain complexes, and hence provide evidence that cristae shape determines mitochondrial respiratory efficiency in mice liver regeneration...This study will focus on the process of liver cells regeneration how the shape of cristae within mitochondria are controlled, uncover how different proteins and other molecules in the inner membranes of mitochondria, interact to determine the cristae structure, consequently respiratory chain complexes function and energy supplies of the mitochondria during mice liver regeneration. Finally, we try to interfere the expression level of the key protein that determins cristae shape to reserch if mice liver regeneration could be promoted in this way.

良好的肝脏再生是治疗肝衰，减少肝脏外科并发症的重要因素。影响肝再生的机制非常复杂，线粒体功能障碍所引起的能量供给不足是重要原因，但机理仍不清楚。本课题组的前期工作（J Hepatol. 2015，Am J Transplant. 2012）表明：严重肝损害时肝细胞线粒体形态发生变化、ATP供应减少，肝再生受到抑制，通过线粒体再生能增加能量供应促进再生。我们最新的研究还发现线粒体嵴的形态结构变化对能量供应有着巨大影响。Mitofilin、呼吸链复合体Ⅳ的亚基Cox17、F0F1-ATP合酶等是参与调控嵴形态的重要因素，但其调控机理尚不明确。本课题将在前期研究的基础上，运用小鼠肝切除模型，通过透射电镜、活体线粒体显影技术，阐明线粒体嵴的形态结构变化规律；运用多种分子生物学技术，揭示其调控机制及对能量供应的影响，寻求有效地干预手段，增加肝再生。

良好的肝脏再生是治疗肝衰，减少肝脏外科并发症的重要因素。影响肝再生的机制非常复杂，线粒体功能障碍所引起的能量供给不足是重要原因，但机理仍不清楚。我们最新的研究还发现线粒体嵴的形态结构变化对能量供应有着巨大影响。Mitofilin、呼吸链复合体Ⅳ的亚基Cox17、F0F1-ATP合酶等是参与调控嵴形态的重要因素。本课题已经前期研究的基础上，运用小鼠肝切除模型，通过透射电镜、活体线粒体显影技术，阐明了线粒体嵴的形态结构变化规律；运用多种分子生物学技术，揭示其调控机制及对能量供应的影响，并寻求有效地干预手段，增加肝再生。我们发现线粒体Grsf1与Mfn2蛋白在线粒体能量代谢，调控线粒体结构，线粒体自噬以及脂肪代谢，凋亡，糖代谢，内质网应激中的重要作用并进行了验证，同时找到调控Mfn2上游的miRNA。同时进行了药物干预研究。为寻求促进肝再生的手段提供新的科学依据。