Lardong Jennifer A, Driller Jan H, Depner Harald, Weise Christoph, Petzoldt Astrid, Wahl Markus C, Sigrist Stephan J, Loll Bernhard
Institut für Chemie und Biochemie Abteilung Strukturbiochemie, Freie Universität Berlin, Takustrasse 6, 15195 Berlin, Germany.
Biologie Abteilung Genetik, Freie Universität Berlin, Takustrasse 6, 15195 Berlin, Germany.
Acta Crystallogr F Struct Biol Commun. 2015 Jan 1;71(Pt 1):34-40. doi: 10.1107/S2053230X1402617X.
Rab GTPases belong to the large family of Ras proteins. They act as key regulators of membrane organization and intracellular trafficking. Functionally, they act as switches. In the active GTP-bound form they can bind to effector proteins to facilitate the delivery of transport vesicles. Upon stimulation, the GTP is hydrolyzed and the Rab proteins undergo conformational changes in their switch regions. This study focuses on Rab2 and Rab3 from Drosophila melanogaster. Whereas Rab2 is involved in vesicle transport between the Golgi and the endoplasmatic reticulum, Rab3 is a key player in exocytosis, and in the synapse it is involved in the assembly of the presynaptic active zone. Here, high-resolution crystal structures of Rab2 and Rab3 in complex with GMPPNP and Mg2+ are presented. In the structure of Rab3 a modified cysteine residue is observed with an enigmatic electron density attached to its thiol function.
Rab GTP酶属于Ras蛋白大家族。它们是膜组织和细胞内运输的关键调节因子。在功能上，它们起着开关的作用。处于活性GTP结合形式时，它们可以与效应蛋白结合，以促进运输小泡的递送。受到刺激后，GTP被水解，Rab蛋白在其开关区域发生构象变化。本研究聚焦于黑腹果蝇的Rab2和Rab3。Rab2参与高尔基体和内质网之间的小泡运输，而Rab3是胞吐作用的关键参与者，在突触中它参与突触前活性区的组装。在此，展示了Rab2和Rab3与GMPPNP和Mg2+复合物的高分辨率晶体结构。在Rab3的结构中，观察到一个修饰的半胱氨酸残基，其硫醇功能上附着有神秘的电子密度。
