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3D structure of Syk kinase determined by single-particle electron microscopy.

ABSTRACT: The cytoplasmic Syk kinase plays key roles in immune responses and comprises two N-terminal regulatory Src homology 2 (SH2) domains followed by a catalytic region. Atomic structures of these domains have only been solved in isolation. To gain insights into the three-dimensional structure of full-length Syk, we have used single-particle electron microscopy. Syk acquires a closed conformation resembling the inhibited structure of Zap-70, another member of the Syk family. Such configuration suggests an inhibition of the N-terminal domains on its catalytic activity. The phosphotyrosine binding pockets of both SH2 domains are not occluded and they could interact with other phosphoproteins.

SUBMITTER: Arias-Palomo E

PROVIDER: S-EPMC2186377 | biostudies-literature | 2007 Dec

REPOSITORIES: biostudies-literature

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3D structure of Syk kinase determined by single-particle electron microscopy.

Arias-Palomo Ernesto E Recuero-Checa María A MA Bustelo Xosé R XR Llorca Oscar O

Biochimica et biophysica acta 20071026 12

The cytoplasmic Syk kinase plays key roles in immune responses and comprises two N-terminal regulatory Src homology 2 (SH2) domains followed by a catalytic region. Atomic structures of these domains have only been solved in isolation. To gain insights into the three-dimensional structure of full-length Syk, we have used single-particle electron microscopy. Syk acquires a closed conformation resembling the inhibited structure of Zap-70, another member of the Syk family. Such configuration suggest ...[more]

PMID: 18021750

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