3N89

KH domains

Summary for 3N89

• Entry DOI: 10.2210/pdb3n89/pdb
• Descriptor: Defective in germ line development protein 3, isoform a (2 entities in total)
• Functional Keywords: kh domains, rna binding, germline development, cell cycle
• Biological source: Caenorhabditis elegans (nematode)
• Total number of polymer chains: 2
• Total formula weight: 85753.92

Authors

Nakel, K.,Hartung, S.A.,Bonneau, F.,Eckmann, C.R.,Conti, E. (deposition date: 2010-05-28, release date: 2010-09-22, Last modification date: 2024-02-21)

Primary citation

Nakel, K.,Hartung, S.A.,Bonneau, F.,Eckmann, C.R.,Conti, E.
Four KH domains of the C. elegans Bicaudal-C ortholog GLD-3 form a globular structural platform.
Rna, 16:2058-2067, 2010

PubMed Abstract: Caenorhabditis elegans GLD-3 is a five K homology (KH) domain-containing protein involved in the translational control of germline-specific mRNAs during embryogenesis. GLD-3 interacts with the cytoplasmic poly(A)-polymerase GLD-2. The two proteins cooperate to recognize target mRNAs and convert them into a polyadenylated, translationally active state. We report the 2.8-Å-resolution crystal structure of a proteolytically stable fragment encompassing the KH2, KH3, KH4, and KH5 domains of C. elegans GLD-3. The structure reveals that the four tandem KH domains are organized into a globular structural unit. The domains are involved in extensive side-by-side interactions, similar to those observed in previous structures of dimeric KH domains, as well as head-to-toe interactions. Small-angle X-ray scattering reconstructions show that the N-terminal KH domain (KH1) forms a thumb-like protrusion on the KH2-KH5 unit. Although KH domains are putative RNA-binding modules, the KH region of GLD-3 is unable in isolation to cross-link RNA. Instead, the KH1 domain mediates the direct interaction with the poly(A)-polymerase GLD-2, pointing to a function of the KH region as a protein-protein interaction platform.

PubMed: 20823118
DOI: 10.1261/rna.2315010

Experimental method

X-RAY DIFFRACTION (2.789 Å)