NSF-BSF: Unraveling the molecular determinants of protein oligomerization

生命的复杂性取决于生物分子将自己组织成更高级功能结构的能力。该项目将研究进化过程如何塑造单个蛋白质自组装成复杂结构的能力，然后产生新的生物分子功能，而不是单个蛋白质本身。从这项研究中获得的见解将有助于蛋白质工程尝试从头创建或扩展酶和其他结构蛋白的功能。该项目还将为K-12教师提供支持和资源，以加强亚特兰大（克莱顿公司）社会经济挑战部分的STEM参与。我们预计，教师层面更强的研究素养将激发K-12学生对科学展览等STEM活动的更大兴趣和参与，从而为中学后教育做好更好的准备。本项目将特别关注蛋氨酸S-腺苷转移酶（MAT），这是一种重要的中央代谢同源四聚体酶，其特征是同源物之间四级结构完整性的高度变异性。该研究将评估MAT折叠和（解）组装的热力学和动力学，单个MAT亚基对分子伴侣的折叠依赖性，中间MAT子复合物的聚集倾向，以及组装的MAT复合物的细胞内周转和活性。现存序列的比较分析将与连接祖先和衍生状态的中间步骤的祖先序列重建相补充。该项目将产生细菌菌株，其中编码内源性MAT同聚体的基因被现存或祖先重建的直系同源物取代，使菌株在各种环境条件下进行实验室进化，并在实验室进化的限制下尽可能确定适应的遗传，结构，功能和系统决定因素。通过这种多方面的方法，该项目将使同聚体进化的基因型-表型-适应性联系起来。该项目由生物科学理事会分子和细胞生物科学部的遗传机制和分子生物物理学项目共同资助。该合作项目由美国/以色列项目得到美国国家科学基金会和以色列两国科学基金会的支持，这一奖项体现了NSF的法定基金会的使命是履行其使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评价，被认为值得支持。

The complexity of life is predicated on the ability of biomolecules to organize themselves into higher-order functional structures. This project will investigate how evolutionary processes shape the ability of individual proteins to self-assemble into complex structures that then generate new biomolecular functionalities than possible for the individual proteins themselves. Insights gained from this research will be useful for protein engineering attempts to create de novo or expanded functionalities of enzymes and other structural proteins. The project will also provide support and resources for K-12 teachers to enhance STEM participation in a socioeconomically challenged section of Atlanta (Clayton Co.). We anticipate that stronger research literacy at the teacher level will generate greater interest and participation of K-12 students in STEM activities such as science fairs, resulting in better preparation for post-secondary education.This project will specifically focus on methionine S-adenosyltransferases (MATs), an essential homo-tetrameric enzyme of central metabolism characterized by high variability in quaternary structure integrity among its homologs. The research will assess thermodynamics and kinetics of MAT folding and (dis)assembly, folding dependency of individual MAT subunits on molecular chaperones, aggregation propensity of intermediate MAT sub-complexes, and the intracellular turnover and activity of assembled MAT complexes. Comparative analysis of extant sequences will be complemented with ancestral sequence reconstruction of the intermediate steps linking ancestral and derived states. The project will generate bacterial strains in which genes encoding the endogenous MAT homomers are replaced with extant or ancestrally reconstructed orthologs, subject the strains to laboratory evolution in a variety of environmental conditions, and identify the genetic, structural, functional and systems determinants of adaptation as best possible given the constraints of laboratory evolution. Through this multifaceted approach, the project will enable a genotype-phenotype-fitness connection for homomer evolution.This project is jointly funded by the Genetic Mechanisms an.d Molecular Biophysics programs of the Molecular and Cellular Biosciences Division in the Biological Sciences Directorate.This collaborative US/Israel project is supported by the US National Science Foundation and the Israeli Binational Science Foundation.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.