44 research outputs found
NF kappa B induces overexpression of bovine FcRn: a novel mechanism that further contributes to the enhanced immune response in genetically modified animals carrying extra copies of FcRn
Among the many functions of the neonatal Fc receptor (FcRn) for
IgG, it binds to IgG-opsonized antigen complexes and propagates
their traffic into lysosomes where antigen processing occurs. We
previously reported that transgenic (Tg) mice and rabbits that
carry multiple copies and overexpress FcRn have augmented
humoral immune responses. Nuclear factor-kappa B (NFκB) is a
critical molecule in the signaling cascade in the immune
response. NFκB induces human FcRn expression and our previous in
silico analysis suggested NFκB binding sites in the promoter
region of the bovine (b) FcRn α-chain gene (FCGRT). Here, we
report the identification of three NFκB transcription binding
sites in the promoter region of this gene using luciferase
reporter gene technology, electromobility shift assay and
supershift analysis. Stimulation of primary bovine endothelial
cells with the Toll like receptor-4 ligand lipopolysaccharide
(LPS), which mediates its effect via NFκB, resulted in rapid
upregulation of the bFcRn expression and a control gene, bovine
E-selectin. This rapid bFcRn gene induction was also observed in
the spleen of bFcRn Tg mice treated with intraperitoneally
injected LPS, analyzed by northern blot analysis. Finally, NFκB-
mediated bFcRn upregulation was confirmed at the protein level
in macrophages isolated from the bFcRn Tg mice using flow
cytometry with a newly developed FcRn specific monoclonal
antibody that does not cross-react with the mouse FcRn. We
conclude that NFκB regulates bFcRn expression and thus optimizes
its functions, e.g., in the professional antigen presenting
cells, and contributes to the much augmented humoral immune
response in the bFcRn Tg mice
A unique haplotype of RCCX copy number variation: from the clinics of congenital adrenal hyperplasia to evolutionary genetics.
There is a difficulty in the molecular diagnosis of congenital adrenal hyperplasia (CAH) due to the c.955C>T (p.(Q319*), formerly Q318X, rs7755898) variant of the CYP21A2 gene. Therefore, a systematic assessment of the genetic and evolutionary relationships between c.955C>T, CYP21A2 haplotypes and the RCCX copy number variation (CNV) structures, which harbor CYP21A2, was performed. In total, 389 unrelated Hungarian individuals with European ancestry (164 healthy subjects, 125 patients with non-functioning adrenal incidentaloma and 100 patients with classical CAH) as well as 34 adrenocortical tumor specimens were studied using a set of experimental and bioinformatic methods. A unique, moderately frequent (2%) haplotypic RCCX CNV structure with three repeated segments, abbreviated to LBSASB, harboring a CYP21A2 with a c.955C>T variant in the 3'-segment, and a second CYP21A2 with a specific c.*12C>T (rs150697472) variant in the middle segment occurred in all c.955C>T carriers with normal steroid levels. The second CYP21A2 was free of CAH-causing mutations and produced mRNA in the adrenal gland, confirming its functionality and ability to rescue the carriers from CAH. Neither LBSASB nor c.*12C>T occurred in classical CAH patients. However, CAH-causing CYP21A2 haplotypes with c.955C>T could be derived from the 3'-segment of LBSASB after the loss of functional CYP21A2 from the middle segment. The c.*12C>T indicated a functional CYP21A2 and could distinguish between non-pathogenic and pathogenic genomic contexts of the c.955C>T variant in the studied European population. Therefore, c.*12C>T may be suitable as a marker to avoid this genetic confound and improve the diagnosis of CAH
More about the comparison of local and non-local NN interaction models
The effect of non-locality in the NN interaction with an off-energy shell
character has been studied in the past in relation with the possibility that
some models could be approximately phase-shifts equivalent. This work is
extended to a non-locality implying terms that involve an anticommutator with
the operator p^2. It includes both scalar and tensor components. The most
recent ``high accuracy'' models are considered in the analysis. After studying
the deuteron wave functions, electromagnetic properties of various models are
compared with the idea that these ones differ by their non-locality but are
equivalent up to a unitary transformation. It is found that the extra non-local
tensor interaction considered in this work tends to re-enforce the role of the
term considered in previous works, allowing one to explain almost completely
the difference in the deuteron D-state probabilities evidenced by the
comparison of the Bonn-QB and Paris models for instance. Conclusions for the
effect of the non-local scalar interaction are not so clear. In many cases, it
was found that these terms could explain part of the differences that the
comparison of predictions for various models evidences but cases where they
could not were also found. Some of these last ones have been analyzed in order
to pointing out the origin of the failure.Comment: 32 pages, 24 figure
Variational Calculation on A=3 and 4 Nuclei with Non-Local Potentials
The application of the hyperspherical harmonic approach to the case of
non-local two-body potentials is described. Given the properties of the
hyperspherical harmonic functions, there are no difficulties in considering the
approach in both coordinate and momentum space. The binding energies and other
ground state properties of A=3 and 4 nuclei are calculated using the CD Bonn
2000 and N3LO two-body potentials. The results are shown to be in excellent
agreement with corresponding ones obtained by other accurate techniques.Comment: 12 pages, 6 tables, RevTex
Analyzing power in nucleon-deuteron scattering and three-nucleon forces
Three-nucleon forces have been considered to be one possibility to resolve
the well known discrepancy between experimental values and theoretical
calculations of the nucleon analyzing power in low energy nucleon-deuteron
scattering. In this paper, we investigate possible effects of two-pion exchange
three-nucleon forces on the analyzing power and the differential cross section.
We found that the reason for different effects on the analyzing power by
different three-nucleon forces found in previous calculations is related to the
existence of the contact term. Effects of some variations of two-pion exchange
three-nucleon forces are investigated. Also, an expression for the measure of
the nucleon analyzing power with quartet P-wave phase shifts is presented.Comment: 11 pages including 2 eps figures, use epsfig.sty, to appear in Phys.
Rev.
A ligand-based system for receptor-specific delivery of proteins
Gene delivery using vector or viral-based methods is often limited by technical and safety barriers. A promising alternative that circumvents these shortcomings is the direct delivery of proteins into cells. Here we introduce a non-viral, ligand-mediated protein delivery system capable of selectively targeting primary skin cells in-vivo. Using orthologous self-labelling tags and chemical cross-linkers, we conjugate large proteins to ligands that bind their natural receptors on the surface of keratinocytes. Targeted CRE-mediated recombination was achieved by delivery of ligand cross-linked CRE protein to the skin of transgenic reporter mice, but was absent in mice lacking the ligand\u2019s cell surface receptor. We further show that ligands mediate the intracellular delivery of Cas9 allowing for CRISPR-mediated gene editing in the skin more efficiently than adeno-associated viral gene delivery. Thus, a ligand-based system enables the effective and receptor-specific delivery of large proteins and may be applied to the treatment of skin-related genetic diseases
Nucleon-Nucleon Interaction: A Typical/Concise Review
Nearly a recent century of work is divided to Nucleon-Nucleon (NN)
interaction issue. We review some overall perspectives of NN interaction with a
brief discussion about deuteron, general structure and symmetries of NN
Lagrangian as well as equations of motion and solutions. Meanwhile, the main NN
interaction models, as frameworks to build NN potentials, are reviewed
concisely. We try to include and study almost all well-known potentials in a
similar way, discuss more on various commonly used plain forms for two-nucleon
interaction with an emphasis on the phenomenological and meson-exchange
potentials as well as the constituent-quark potentials and new ones based on
chiral effective field theory and working in coordinate-space mostly. The
potentials are constructed in a way that fit NN scattering data, phase shifts,
and are also compared in this way usually. An extra goal of this study is to
start comparing various potentials forms in a unified manner. So, we also
comment on the advantages and disadvantages of the models and potentials partly
with reference to some relevant works and probable future studies.Comment: 85 pages, 5 figures, than the previous v3 edition, minor changes, and
typos fixe
Both Positive and Negative Selection Pressures Contribute to the Polymorphism Pattern of the Duplicated Human CYP21A2 Gene.
The human steroid 21-hydroxylase gene (CYP21A2) participates in cortisol and aldosterone biosynthesis, and resides together with its paralogous (duplicated) pseudogene in a multiallelic copy number variation (CNV), called RCCX CNV. Concerted evolution caused by non-allelic gene conversion has been described in great ape CYP21 genes, and the same conversion activity is responsible for a serious genetic disorder of CYP21A2, congenital adrenal hyperplasia (CAH). In the current study, 33 CYP21A2 haplotype variants encoding 6 protein variants were determined from a European population. CYP21A2 was shown to be one of the most diverse human genes (HHe=0.949), but the diversity of intron 2 was greater still. Contrary to previous findings, the evolution of intron 2 did not follow concerted evolution, although the remaining part of the gene did. Fixed sites (different fixed alleles of sites in human CYP21 paralogues) significantly accumulated in intron 2, indicating that the excess of fixed sites was connected to the lack of effective non-allelic conversion and concerted evolution. Furthermore, positive selection was presumably focused on intron 2, and possibly associated with the previous genetic features. However, the positive selection detected by several neutrality tests was discerned along the whole gene. In addition, the clear signature of negative selection was observed in the coding sequence. The maintenance of the CYP21 enzyme function is critical, and could lead to negative selection, whereas the presumed gene regulation altering steroid hormone levels via intron 2 might help fast adaptation, which broadly characterizes the genes of human CNVs responding to the environment