The mechanism of PDGF-receptor β (PDGFRβ) activation was explored by analyzing the properties mutant receptors designed based on crystal structure extracellular region related receptor tyrosine kinase KIT/stem cell factor receptor. Here, we demonstrate that PDGF-induced a PDGFRβ mutated in Arg-385 or Glu-390 D4 (the fourth Ig-like domain region) compromised, resulting impairment variety cellular responses. These experiments homotypic interactions probably mediated salt bridges between and...

Interaction between the mammalian cell polarity proteins mInsc (mammalian homologue of Inscuteable) and Leu-Gly-Asn repeat-enriched protein (LGN), as well that their respective Drosophila homologues Inscuteable Partner (Pins), plays crucial roles in mitotic spindle orientation, a process contributing to asymmetric division. Here, we report crystal structure LGN-binding domain (LBD) human complexed with N-terminal tetratricopeptide repeat (TPR) motifs LGN at 2.6-Å resolution. In complex,...

The phagocyte NADPH oxidase plays a crucial role in host defense against microbial infections by generating reactive oxygen species. It is multisubunit enzyme composed of membrane-bound flavocytochrome b558 as well cytosolic components, including p47phox, which essential for assembly the complex. When phagocytes are activated, components translocate to due binding tandem Src homology 3 (SH3) domains p47phox proline-rich region p22phox, subunit b558. Using NMR titration, we first identified...

Lacrimo-auriculo-dento-digital (LADD) syndrome is characterized by abnormalities in lacrimal and salivary glands, teeth, the distal limbs. Genetic studies have implicated heterozygous mutations fibroblast growth factor 10 (FGF10) FGF receptor 2 (FGFR2) LADD syndrome. However, it not clear whether (LADD mutations) are gain- or loss-of-function mutations. In order to reveal molecular mechanism underlying syndrome, we compared biological properties of FGF10 FGFR2 mutants activities their normal...

The phagocyte NADPH oxidase is a multisubunit enzyme responsible for the production of reactive oxygen species. p47 phox cytosolic component and plays an important role in assembly activated complex. structural determination tandem SH3 domains crucial elucidation molecular mechanism activation . We determined X‐ray crystal structure with polybasic/autoinhibitory region (PBR/AIR) GAPPR sequence involved PBR/AIR forms left‐handed polyproline type‐II helix (PPII) interacts conserved binding...

The phagocyte NADPH oxidase is a multisubunit enzyme responsible for the generation of superoxide anions (O2.) that kill invading microorganisms. p47phox cytosolic subunit oxidase, which plays crucial role in assembly activated complex. molecular shapes tandem SH3 domains either with or without polybasic/autoinhibitory region (PBR/AIR) at C terminus were studied using small angle x-ray scattering. PBR/AIR formed compact globular structure, whereas lacking an elongated structure. Alignment...

Protein N-glycosylation occurs in the three domains of life. Oligosaccharyltransferase (OST) transfers glycan to asparagine sequon. The catalytic subunit OST is called STT3 eukaryotes, AglB archaea, and PglB eubacteria. genome a hyperthermophilic archaeon, Archaeoglobus fulgidus, encodes paralogs. Two them are shortest AglBs across all We determined crystal structure C-terminal globular domain smallest identify minimal structural unit. lacked β-barrel-like structure, which had been found...

The phagocyte NADPH oxidase, dormant in resting cells, is activated during phagocytosis to produce superoxide, a precursor of microbicidal oxidants. membrane-integrated protein gp91(phox) serves as the catalytic core, because it contains complete electron-transporting apparatus from molecular oxygen for superoxide production. Activation requires cytosolic proteins p67(phox), p47(phox), and Rac (a small GTPase). comprising 526 amino acids, moves upon cell stimulation membrane together with...

The superoxide-producing phagocyte NADPH oxidase can be reconstituted in a cell-free system. activity of is dependent on FAD, but the physiological status FAD not fully elucidated. To clarify role oxidase, FAD-free full-length recombinant p47phox, p67phox, p40phox, and Rac were prepared, was with these proteins purified cytochrome b558 (cyt b558) different amounts FAD. A remarkably high activity, over 100 μmol/s/μmol heme, obtained cyt b558, ternary complex (p47-p67-p40phox), Rac. From...

The phagocyte NADPH oxidase, crucial for innate immunity, is dormant in resting cells, but becomes activated during phagocytosis to produce superoxide, a precursor of microbicidal oxidants. In activation the multidomain protein p67<sup>phox</sup>plays central role: it translocates membrane as ternary complex with p47<sup>phox</sup>and p40<sup>phox</sup>, and interacts small GTPase Rac assemble membrane-integrated catalytic gp91<sup>phox</sup>,...

Proper mitotic spindle orientation requires that astral microtubules are connected to the cell cortex by microtubule-binding protein NuMA, which is recruited from cytoplasm. Cortical recruitment of NuMA at least partially mediated via direct binding adaptor LGN. LGN normally adopts a closed conformation an intramolecular interaction between its N-terminal NuMA-binding domain and C-terminal region contains four GoLoco (GL) motifs, each capable membrane-anchored Gαi subunit heterotrimeric G...

The adaptor protein LGN interacts via the N-terminal domain comprising eight tetratricopeptide-repeat (TPR) motifs with its partner proteins mInsc, NuMA, Frmpd1 and Frmpd4 in a mutually exclusive manner. Here, crystal structure of TPR complex human is described at 1.5 Å resolution. In complex, LGN-binding region (amino-acid residues 990-1011) adopts an extended that runs antiparallel to along concave surface superhelix formed by motifs. Comparison previously determined structures LGN-Frmpd1,...

p47phox is a cytosolic component of the phagocyte NADPH oxidase, which responsible for production superoxide kills invasive microorgamisms. A recombinant form histidine-tagged tandem SH3 domain p47phox-containing polybasic autoinhibited region was expressed in Escherichia coli and purified crystallized by sitting-drop vapour-diffusion method at 293 K using polyethylene glycol 6000 as precipitant. Diffraction data were collected to 2.15 Å resolution 100 synchrotron radiation. The crystal...

Tubulin acetylation by the enzyme αTAT1 regulates microtublules that participate in various events including cell division and cellular transport. Here we show quantity control of its cofactor (acetyl-CoA CoA)-mediated stabilization molecular mechanism for substrate recognition