Haloferax volcanii microproteins that contain two CPXCG motifs indicative for one-domain zinc finger proteins

本项目是SPP2002“原核生物中的小蛋白”重点项目，主要研究嗜盐古细菌中含有两个C(P)XCG基序的非常小的蛋白，因此是单结构域锌指蛋白。在第一个授予期，16个缺失突变体的表型特征揭示了盐古菌C(P)XCG蛋白的高生物学意义。对其中一个蛋白HVO_2753进行了详细的表征，并求解了其核磁共振溶液结构。在第二个授予期，将产生更多C(P)XCG蛋白基因的缺失突变体集合并进行表征。将建立一种新的“隐藏硫醇蛋白质组学”方法，并将其用于平行表征不同环境条件下小锌指蛋白的差异生产。HVO_2753和其他一些具有高生物学意义的C(P)XCG蛋白将进一步详细表征，例如，将揭示选定的单个氨基酸对蛋白质在体内功能的重要性，确定相互作用伙伴，并进行进一步的结构研究。总之，该项目将使人们对小锌指蛋白在盐古菌中的生物学作用和分子机制有前所未有的了解。

This project in the framework of the Priority Program SPP2002 “Small proteins in prokaryotes” concentrates on very small proteins of the halophilic archaeaon Haloferax volcanii, which contain two C(P)XCG motifs, and, thus, are one-domain zinc finger proteins. In the first granting period, phenotypic characterization of 16 deletion mutants has revealed the high biological significance of haloarchaeal C(P)XCG proteins. One protein, HVO_2753, has been characterized in detail, and its NMR solution structure was solved.In the second granting period, a deletion mutant collection of further C(P)XCG protein genes will be generated and characterized. A novel approach of “hidden thiol proteomics” will be established and used for the parallel characterization of differential production of small zinc finger proteins under various environmental conditions. HVO_2753 and a few additional C(P)XCG proteins of high biological significance will be further characterized in detail, e.g. the importance of selected single amino acids for protein function in vivo will be unraveled, interaction partners will be identified, and further structural studies will be performed. In summary, the project will lead to an unprecedented insight into the biological roles and molecular mechanisms of small zinc finger proteins in haloarchaea.