کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2051415 1074200 2005 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
High resolution crystal structures of human Rab4a in its active and inactive conformations
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک دانش گیاه شناسی
پیش نمایش صفحه اول مقاله
High resolution crystal structures of human Rab4a in its active and inactive conformations
چکیده انگلیسی

The Ras-related human GTPase Rab4a is involved in the regulation of endocytosis through the sorting and recycling of early endosomes. Towards further insight, we have determined the three-dimensional crystal structure of human Rab4a in its GppNHp-bound state to 1.6 Å resolution and in its GDP-bound state to 1.8 Å resolution, respectively. Despite the similarity of the overall structure with other Rab proteins, Rab4a displays significant differences. The structures are discussed with respect to the recently determined structure of human Rab5a and its complex with the Rab5-binding domain of the bivalent effector Rabaptin-5. The Rab4 specific residue His39 modulates the nucleotide binding pocket giving rise to a reduced rate for nucleotide hydrolysis and exchange. In comparison to Rab5, Rab4a has a different GDP-bound conformation within switch 1 region and displays shifts in position and orientation of the hydrophobic triad. The observed differences at the S2–L3–S3 region represent a new example of structural plasticity among Rab proteins and may provide a structural basis to understand the differential binding of similar effector proteins.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: FEBS Letters - Volume 579, Issue 13, 23 May 2005, Pages 2821–2829
نویسندگان
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