BRC-BIO: Harnessing sequence features to understand and manipulate the function of reflectin proteins in iridescence

反射蛋白是鱿鱼和章鱼等头足类动物光散射纳米结构的关键组成部分。这些类型结构的一个突出例子是可调且可逆的彩虹反射器。这些蛋白质存在于特定的细胞中，称为虹膜细胞，存在于某些鱿鱼物种的皮肤中。这些细胞中的虹彩是由反射蛋白的可逆磷酸化驱动的。由于它们迷人的特性，反射蛋白和包含它们的光操纵组件已经成为旨在开发下一代活性生物光子生物材料和纳米技术的一系列工作的生物灵感。然而，反射组装的分子细节，以及可调谐性的机制和演变，仍然知之甚少。反射蛋白具有独特的氨基酸序列，这可能是使它们能够发挥其生物光子功能的关键。这个项目试图解开反射蛋白的独特氨基酸的组装特性和生物光子功能的多个功能的影响。美国索卡大学的本科生将在与PI合作并为该项目做出贡献时接受科学培训和研究经验。PI还将通过提供基于课程的本科生研究体验，使学生能够参与涉及反思的真实学期研究项目，从而使更广泛的本科生群体参与研究。反射蛋白质是本质上无序的嵌段共聚物。最近的工作表明，反射蛋白进行液-液相分离，形成生物分子凝聚物。虽然许多蛋白质的冷凝物形成与一系列细胞过程有关，但反射蛋白在其作为可调生物光子学驱动器的生物学作用以及其组装成可预测大小的动态被捕球形组件的观察能力方面是独特的。PI和本科生同事将使用一系列技术（包括显微镜，光散射等）来表征反射蛋白，以阐明将反射蛋白序列与其组装特性联系起来的隐藏设计原理。这些发现的设计原则将被应用于合理地重新设计反射蛋白，以提高其作为可调生物材料的能力。PI将扩展单组分和多组分反射蛋白缩合物的表征到真核细胞内，阐明这些蛋白质在更复杂的细胞环境中的行为。这个项目将提供洞察可能的机制，可调虹彩的演变在loliginid鱿鱼，也将产生更深入的了解分子机制，驱动反射可调组装和动态逮捕，该奖项反映了NSF的法定使命，并通过评估被认为值得支持使用基金会的知识价值和更广泛的影响审查标准。

Reflectin proteins are key components of light-scattering nanostructures in cephalopods such as squid and octopuses. A prominent example of these types of structures is the tunable and reversibly iridescent reflectors. These proteins are found within specialized cells, called iridocytes, present in the skin of certain squid species. Iridescence in these cells is driven by reversible phosphorylation of reflectins. Due to their fascinating properties, reflectins and the light-manipulating assemblies that contain them have served as bioinspiration for a range of work aiming to develop next-generation active biophotonic biomaterials and nanotechnologies. However, the molecular details of reflectin assembly, as well as the mechanisms and evolution of tunability, remains poorly understood. Reflectin proteins have a unique amino acid sequence that is likely critical in enabling them to serve their biophotonic functions. This project seeks to disentangle the effects of multiple features within reflectin's unique amino acid to its assembly properties and biophotonic function. Soka University of America undergraduates will receive scientific training and research experience as they work with the PI and contribute to this project. The PI will also engage a broader group of undergraduates in research by offering a Course-based Undergraduate Research Experience that enables students to participate in an authentic semester-long research project involving reflectins. Reflectins proteins are intrinsically disordered block copolymers. Recent work suggests that reflectin proteins undergo liquid-liquid phase separation to form biomolecular condensates. While condensate formation by many proteins has been linked to a range of cellular processes, reflectins are unique in their biological role as drivers of tunable biophotonics and in their observed ability to assemble into dynamically arrested spherical assemblies of predictable size. The PI and undergraduate coworkers will characterize reflectin proteins using a range of techniques including microscopy, light scattering, and more, to elucidate the hidden design principles that link reflectin's sequence to its assembly properties. These discovered design principles will then be applied to rationally re-engineer reflectin to improve its capability as a tunable biomaterial. The PI will extend the characterization of single- and multi-component reflectin condensates to within eukaryotic cells, elucidating how these proteins behave within more complex cellular environments. This project will offer insight into possible mechanisms for the evolution of tunable iridescence in loliginid squids and will also produce a deeper understanding of the molecular mechanisms that drive reflectin tunable assembly and dynamic arrest, providing knowledge that may be potentially applied towards the development of future biophotonic technologies and biomaterials.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.