The microtubule-associated protein tau forms disease-specific filamentous aggregates in several different neurodegenerative diseases. In order to understand how tau undergoes misfolding into a specific filament type and to control this process for drug development purposes, it is crucial to study in vitro tau aggregation methods and investigate the structures of the obtained filaments at the atomic level. Here, we used the tau fragment dGAE, which aggregates spontaneously, to seed the formation of full-length tau filaments. The structures of dGAE and full-length tau filaments were investigated by magic-angle spinning (MAS) solid-state NMR, showing that dGAE allows propagation of a chronic traumatic encephalopathy (CTE)-like fold to the full-length tau. The obtained filaments efficiently seeded tau aggregation in HEK293T cells. This work demonstrates that in vitro preparation of disease-specific types of full-length tau filaments is feasible.

• Klíčová slova
• NMR spectroscopy, dGAE fragment, filamentous aggregates, tau protein, tauopathies,
• MeSH
• chronická traumatická encefalopatie * metabolismus   patologie   MeSH
• HEK293 buňky MeSH
• lidé MeSH
• proteiny tau * metabolismus   chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• proteiny tau * MeSH

BACKGROUND: The mammalian Major Histocompatibility Complex (MHC) is a genetic region containing highly polymorphic genes with immunological functions. MHC class I and class II genes encode antigen-presenting molecules expressed on the cell surface. The MHC class II sub-region contains genes expressed in antigen presenting cells. The antigen binding site is encoded by the second exon of genes encoding antigen presenting molecules. The exon 2 sequences of these MHC genes have evolved under the selective pressure of pathogens. Interspecific differences can be observed in the class II sub-region. The family Equidae includes a variety of domesticated, and free-ranging species inhabiting a range of habitats exposed to different pathogens and represents a model for studying this important part of the immunogenome. While equine MHC class II DRA and DQA loci have received attention, the genetic diversity and effects of selection on DRB and DQB loci have been largely overlooked. This study aimed to provide the first in-depth analysis of the MHC class II DRB and DQB loci in the Equidae family. RESULTS: Three DRB and two DQB genes were identified in the genomes of all equids. The genes DRB2, DRB3 and DQB3 showed high sequence conservation, while polymorphisms were more frequent at DRB1 and DQB1 across all species analyzed. DQB2 was not found in the genome of the Asiatic asses Equus hemionus kulan and E. h. onager. The bioinformatic analysis of non-zero-coverage-bases of DRB and DQB genes in 14 equine individual genomes revealed differences among individual genes. Evidence for recombination was found for DRB1, DRB2, DQB1 and DQB2 genes. Trans-species allele sharing was identified in all genes except DRB1. Site-specific selection analysis predicted genes evolving under positive selection both at DRB and DQB loci. No selected amino acid sites were identified in DQB3. CONCLUSIONS: The organization of the MHC class II sub-region of equids is similar across all species of the family. Genomic sequences, along with phylogenetic trees suggesting effects of selection as well as trans-species polymorphism support the contention that pathogen-driven positive selection has shaped the MHC class II DRB/DQB sub-regions in the Equidae.

• Klíčová slova
• Family Equidae, MHC class II loci, MHC exon 2, Major histocompatibility complex, Positive selection, Selected amino acid sites, Trans-species polymorphism,
• MeSH
• Equidae klasifikace   genetika   MeSH
• fylogeneze MeSH
• hlavní histokompatibilní komplex genetika   MeSH
• molekulární evoluce * MeSH
• polymorfismus genetický * MeSH
• rekombinace genetická MeSH
• selekce (genetika) * MeSH
• vznik druhů (genetika) MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

This study brings new information on major histocompatibility complex (MHC) class III sub-region genes in Old World camels and integrates current knowledge of the MHC region into a comprehensive overview for Old World camels. Out of the MHC class III genes characterized, TNFA and the LY6 gene family showed high levels of conservation, characteristic for MHC class III loci in general. For comparison, an MHC class II gene TAP1, not coding for antigen presenting molecules but functionally related to MHC antigen presenting functions was studied. TAP1 had many SNPs, even higher than the MHC class I and II genes encoding antigen presenting molecules. Based on this knowledge and using new camel genomic resources, we constructed an improved genomic map of the entire MHC region of Old World camels. The MHC class III sub-region shows a standard organization similar to that of pig or cattle. The overall genomic structure of the camel MHC is more similar to pig MHC than to cattle MHC. This conclusion is supported by differences in the organization of the MHC class II sub-region, absence of functional DY genes, different organization of MIC genes in the MHC class I sub-region, and generally closer evolutionary relationships of camel and porcine MHC gene sequences analyzed so far.

• Klíčová slova
• Bactrian camel, MHC, Old World camels, SNP, camels, dromedary, major histocompatibility complex,
• MeSH
• antigeny Ly klasifikace   genetika   MeSH
• fylogeneze MeSH
• hlavní histokompatibilní komplex * MeSH
• jednonukleotidový polymorfismus MeSH
• prasata MeSH
• skot MeSH
• TNF-alfa klasifikace   MeSH
• velbloudi genetika   imunologie   MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny Ly MeSH
• TNF-alfa MeSH

Human tyrosine hydroxylase 1 (hTH1) activity is regulated by phosphorylation of its regulatory domain (RD-hTH1) and by an interaction with the 14-3-3 protein. The RD-hTH1 is composed of a structured region (66-169) preceded by an intrinsically disordered protein region (IDP, hTH1_65) containing two phosphorylation sites (S19 and S40) which are highly relevant for its increase in activity. The NMR signals of the IDP region in the non-phosphorylated, singly phosphorylated (pS40) and doubly phosphorylated states (pS19_pS40) were assigned by non-uniformly sampled spectra with increased dimensionality (5D). The structural changes induced by phosphorylation were analyzed by means of secondary structure propensities. The phosphorylation kinetics of the S40 and S19 by kinases PKA and PRAK respectively were monitored by non-uniformly sampled time-resolved NMR spectroscopy followed by their quantitative analysis.

• Klíčová slova
• Human tyrosine hydroxylase, IDP, Kinetics, NMR, Non-uniform sampling, Phosphorylation, SSP, Time-resolved NMR,
• MeSH
• fosforylace MeSH
• intracelulární signální peptidy a proteiny metabolismus   MeSH
• kinetika MeSH
• lidé MeSH
• magnetická rezonanční spektroskopie metody   MeSH
• protein-serin-threoninkinasy metabolismus   MeSH
• proteinkinasy závislé na cyklickém AMP metabolismus   MeSH
• proteinové domény MeSH
• sekundární struktura proteinů MeSH
• tyrosin-3-monooxygenasa chemie   metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• intracelulární signální peptidy a proteiny MeSH
• MAP-kinase-activated kinase 5 MeSH Prohlížeč
• protein-serin-threoninkinasy MeSH
• proteinkinasy závislé na cyklickém AMP MeSH
• tyrosin-3-monooxygenasa MeSH