Afadin couples RAS GTPases to the polarity rheostat Scribble.

AFDN/Afadin is required for establishment and maintenance of cell-cell contacts and is a unique effector of RAS GTPases. The biological consequences of RAS complex with AFDN are unknown. We used proximity-based proteomics to generate an interaction map for two isoforms of AFDN, identifying the polarity protein SCRIB/Scribble as the top hit.

Structure of the DOCK2-ELMO1 complex provides insights into regulation of the auto-inhibited state.

DOCK (dedicator of cytokinesis) proteins are multidomain guanine nucleotide exchange factors (GEFs) for RHO GTPases that regulate intracellular actin dynamics. DOCK proteins share catalytic (DOCK) and membrane-associated (DOCK) domains. The structurally-related DOCK1 and DOCK2 GEFs are specific for RAC, and require ELMO (engulfment and cell motility) proteins for function.

Structural insights into a 20.8-kDa tegumental-allergen-like (TAL) protein from Clonorchis sinensis.

Survival of Clonorchis sinensis, a cause of human clonorchiasis, requires tegument proteins, which are localized to the tegumental outer surface membrane. These proteins play an important role in a host response and parasite survival. Thus, these proteins are interesting molecular targets for vaccine and drug development.

Crystal structure of Thermoplasma acidophilum XerA recombinase shows large C-shape clamp conformation and cis-cleavage mode for nucleophilic tyrosine.

Site-specific Xer recombination plays a pivotal role in reshuffling genetic information. Here, we report the 2.5 Å crystal structure of XerA from the archaean Thermoplasma acidophilum.

Crystal structure of Legionella pneumophila type IV secretion system effector LegAS4.

The SET domain of LegAS4, a type IV secretion system effector of Legionella pneumophila, is a eukaryotic protein motif involved in histone methylation and epigenetic modulation. The SET domain of LegAS4 is involved in the modification of Lys4 of histone H3 (H3K4) in the nucleolus of the host cell, thereby enhancing heterochromatic rDNA transcription. Moreover, LegAS4 contains an ankyrin repeat domain of unknown function at its C-terminal region.

Structure of the ArgRS-GlnRS-AIMP1 complex and its implications for mammalian translation.

In higher eukaryotes, one of the two arginyl-tRNA synthetases (ArgRSs) has evolved to have an extended N-terminal domain that plays a crucial role in protein synthesis and cell growth and in integration into the multisynthetase complex (MSC). Here, we report a crystal structure of the MSC subcomplex comprising ArgRS, glutaminyl-tRNA synthetase (GlnRS), and the auxiliary factor aminoacyl tRNA synthetase complex-interacting multifunctional protein 1 (AIMP1)/p43. In this complex, the N-terminal domain of ArgRS forms a long coiled-coil structure with the N-terminal helix of AIMP1 and anchors the C-terminal core of GlnRS, thereby playing a central role in assembly of the three components.

Structural and biochemical analysis of a type II free methionine-R-sulfoxide reductase from Thermoplasma acidophilum.

Free methionine-R-sulfoxide reductase (fRMsr) enzymes only reduce the free form of methionine-R-sulfoxide and can be grouped into two types with respect to the number of conserved Cys residues in the active sites. In this work, the crystal structures of type II fRMsr from Thermoplasma acidophilum (TafRMsr), which contains two conserved Cys, have been determined in native form and in a complex with the substrate. The overall structure of TafRMsr consists of a central β-sheet encompassed by a two-α-helix bundle flanking on one side and one small α-helix on the other side.

The crystal structure of arginyl-tRNA synthetase from Homo sapiens.

Arginyl-tRNA synthetase (ArgRS) is a tRNA-binding protein that catalyzes the esterification of L-arginine to its cognate tRNA. L-Canavanine, a structural analog of L-arginine, has recently been studied as an anticancer agent. Here, we determined the crystal structures of the apo, L-arginine-complexed, and L-canavanine-complexed forms of the cytoplasmic free isoform of human ArgRS (hArgRS).