Dynein, a homodimeric protein complex, plays a pivotal role in retrograde transportation along microtubules within cells. It consists of various subunits, among which the light intermediate chain (LIC) performs diverse functions, including cargo adaptor binding. In contrast to the vertebrate LIC homolog LIC1, LIC2 has received relatively limited characterization thus far, despite partially orthogonal functional roles.
View Article and Find Full Text PDFOlduvai protein domains (formerly DUF1220) show the greatest human-specific increase in copy number of any coding region in the genome and are highly correlated with human brain evolution and cognitive disease. The majority of human copies are found within four NBPF genes organized in a variable number of a tandemly arranged three-domain blocks called Olduvai triplets. Here we show that these human-specific Olduvai domains are posttranslationally processed by the furin protease, with a cleavage site occurring once at each triplet.
View Article and Find Full Text PDFThe introduction of the exact nuclear Overhauser enhancement (eNOE) methodology to solution-state nuclear magnetic resonance (NMR) spectroscopy results in tighter distance restraints from NOEs than in convention analysis. These improved restraints allow for higher resolution in structure calculation and even the disentanglement of different conformations of macromolecules. While initial work primarily focused on technical development of the eNOE, structural studies aimed at the elucidation of spatial sampling in proteins and nucleic acids were published in parallel prior to 2018.
View Article and Find Full Text PDFOlduvai protein domains, encoded by the NBPF gene family, are responsible for the largest increase in copy number of any protein-coding region in the human genome. This has spawned various genetics studies which have linked these domains to human brain development and divergence from our primate ancestors, as well as currently relevant cognitive diseases such as schizophrenia and autism spectrum disorder (ASD). There are six separate Olduvai domains which together form the majority of the various protein products of the NBPF genes.
View Article and Find Full Text PDFBiliverdin reductase B (BLVRB) family members are general flavin reductases critical in maintaining cellular redox with recent findings revealing that BLVRB alone can dictate cellular fate. However, as opposed to most enzymes, the BLVRB family remains enigmatic with an evolutionarily changing active site and unknown structural and functional consequences. Here, we applied a multi-faceted approach that combines X-ray crystallography, NMR and kinetics methods to elucidate the structural and functional basis of the evolutionarily changing BLVRB active site.
View Article and Find Full Text PDFMany bacterial pathogens express small G5 domains that exist in the context of various membrane-anchored proteins and these G5 domains have been associated with colonization, cellular adhesion, and biofilm formation. However, despite over a decade since the computational prediction of these G5 domains, many remain uncharacterized, particularly those from Streptococcus pneumoniae. Of five previously predicted G5 domains we found that four of these, all derived from S.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
March 2019
Interleukin-37 (IL-37), a member of the IL-1 family of cytokines, is a fundamental suppressor of innate and acquired immunities. Here, we used an integrative approach that combines biophysical, biochemical, and biological studies to elucidate the unique characteristics of IL-37. Our studies reveal that single amino acid mutations at the IL-37 dimer interface that result in the stable formation of IL-37 monomers also remain monomeric at high micromolar concentrations and that these monomeric IL-37 forms comprise higher antiinflammatory activities than native IL-37 on multiple cell types.
View Article and Find Full Text PDFBiliverdin reductase B (BLVRB) is a newly identified cellular redox regulator that catalyzes the NADPH-dependent reduction of multiple substrates. Through mass spectrometry analysis, we identified high levels of BLVRB in mature red blood cells, highlighting the importance of BLVRB in redox regulation. The BLVRB conformational changes that occur during conezyme/substrate binding and the role of dynamics in BLVRB function, however, remain unknown.
View Article and Find Full Text PDFIgA1 proteases (IgA1P) from diverse pathogenic bacteria specifically cleave human immunoglobulin A1 (IgA1) at the hinge region, thereby thwarting protective host immune responses. Streptococcus pneumoniae (S. pneumoniae) IgA1P shares no sequence conservation with serine or cysteine types of IgA1Ps or other known proteins, other than a conserved HExxH Zn-binding motif (1604-1608) found in metalloproteases.
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