Elucidating the regulatory network of light harvesting in photoheterotrophic microalgae

植物和绿藻的光收集系统已经进化，它们适应了在它们的栖息地遇到的光强度和光谱组成。这些生物体不断受到光源波动和其他影响光合作用表现的环境信号的挑战。过量的光可能特别有害，但植物和微藻配备了不同的适应机制来控制这两个光系统吸收的阳光的处理。许多微藻物种是兼性异养生物，其捕光能力不仅根据普遍的阳光强度进行调整，还根据无机和有机碳源的可用性进行调整。在这个赠款项目中，我们打算调查不同的控制水平，这些水平是随着碳源和光通道的变化而调整光收集能力所需的，并依赖于不同细胞隔间之间的密切相互作用。具体地说，我们想要深入阐明控制捕光蛋白质合成的机制(S)，这是适应光和碳供应变化的反应中的一个关键调控过程。我们将重点研究LHC翻译控制作为调控网络的关键元件，以及这种长期反应与主要短期机制的相互关系，以了解通过核编码因子合成细胞质LHCII的控制机制，协调LHCII翻译的叶绿体和细胞质之间的串扰，以及优化光合作用光捕获的短期和长期光合作用适应机制的整合。

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.