Elucidating the regulatory network of light harvesting in photoheterotrophic microalgae

光收集系统已经在植物和绿色藻类中进化，其适应于在其栖息地中遇到的光强度和光谱组成。这些生物体不断受到波动的光照供应和其他影响光合性能的环境因素的挑战。过量的光可能是特别有害的，但植物和微藻配备了不同的适应机制，以控制在两个光系统中吸收的阳光的处理。许多微藻物种是兼性异养生物，其中光捕获能力不仅根据当时的阳光强度进行调节，而且还根据无机和有机碳源的可用性进行调节。在这个资助项目中，我们打算研究不同的控制水平，这些控制水平是在碳源和光接入变化后调整光捕获能力所需的，并依赖于不同细胞区室之间的密切相互作用。详细地说，我们希望深入阐明控制捕光蛋白合成的机制，这是适应变化的光和碳供应反应中的一个关键调控过程。我们将专注于LHC翻译控制作为调控网络的一个关键要素，以及这种长期响应与主要短期机制的相互关系，以了解细胞溶质LHCII合成的控制机制，通过核编码因子，叶绿体和细胞溶质之间的串扰，协调LHCII翻译和整合的短期和长期光合适应机制，优化光合光捕获。

Light harvesting systems have evolved in plants and green algae, which are adapted to the light intensity and spectral composition encountered in their habitats. These organisms are constantly challenged by a fluctuating light supply and other environmental cues affecting photosynthetic performance. Excess light can be especially harmful, but plants and microalgae are equipped with different acclimation mechanisms to control processing of absorbed sunlight at both photosystems. Many microalgal species are facultative heterotrophs, in which light harvesting capacity is not only adjusted to the prevailing sunlight intensity, but also to the availability of inorganic and organic carbon sources. In this grant project we intend to investigate into distinct control levels that are needed to adjust light harvesting capacity following variations in carbon source as well as light access and rely on a close interaction in between different cellular compartments. In detail we want to deeply elucidate the mechanism(s) controlling light-harvesting protein synthesis, which emerged as a key regulatory process within the acclimation response to altered light and carbon supply. We will focus on LHC translation control as a key element of the regulatory network and the interrelation of this long-term response with major short-term mechanisms to understand the control mechanism for cytosolic LHCII synthesis via nucleus-encoded factors, the crosstalk between chloroplast and cytosol that orchestrates LHCII translation and the integration of short- and long-term photosynthetic acclimation mechanisms for optimizing photosynthetic light capture.