China 
Africa 
Explore chapters and articles related to this topic
Manipulating the Intracellular Trafficking of Nucleic Acids
Published in Kenneth L. Brigham, Gene Therapy for Diseases of the Lung, 2020
Kathleen E. B Meyer, Lisa S. Uyechi, Francis C. Szoka
Nuclear envelope assembly occurs in anaphase and telophase, and begins with dephosphorylation of the putative nuclear envelope receptor, which permits the sequential targeting of membrane components to the chromatin surface. Vesicles (80 to 200 nm in diameter) containing the lamin B receptor, an inner membrane protein, are the first components to initiate the assembly process (167-169). Experiments employing tryptic digestion have shown that vesicle chromatin association requires proteins on both the vesicle and the chromatin to interact for the priming of the spontaneous reassociation of nuclear envelope components (156,166). The fusion of membrane vesicles follows vesicle coating of chromatin, producing a double lipid bilayer structure. Nuclear membrane reassembly then proceeds by the incorporation of NPCs and reassembly of the lamina matrix. Vesicle binding to chromatin is independent of ATP (166); however, vesicle fusion requires the presence of both ATP and GTP (166,170). Vesicle fusion is inhibited by treatment of both cytoplasmic and membrane fractions with NEM, confirming the involvement of protein interaction in vesicle binding, and is inhibited by treatment with the calcium chelator BAPTA suggesting a role of calcium in the fusion process (169).
Immunopathogenesis of Vanishing Bile Duct Syndromes
Published in Gianfranco Alpini, Domenico Alvaro, Marco Marzioni, Gene LeSage, Nicholas LaRusso, The Pathophysiology of Biliary Epithelia, 2020
John M. Vierling, Marius Braun, Haimei Wang
Antinuclear antibodies (ANAs) are detected in approximately 52% of patients with PBC and are the only disease-specific autoantibodies detected in the AMA-negative variant AIC.63 Three PBC-specific ANAs react with autoantigens within the nuclear membrane: 1) gp210, a 210 kDa transmembrane nuclear pore glycoprotein involved in nuclear membrane attachment of pore complexes; 2) nuclear pore glycoprotein p62; and 3) inner nuclear membrane protein lamin B receptor (LBR) that binds nuclear lamins and double-stranded DNA and may anchor nuclear lamins and heterochromatin during interphase. Autoantibodies to gp210 and p62 are mutually exclusive. Although disease specific, the prevalence of these ANAs varies considerably. In contrast to the absence of prognostic significance of AMAs, anti-gp210 autoantibodies were significantly associated with fatality. A minority of patients also have ANAs that react with an antigen referred to as Sp 100, which colocalize with promyelocytic leukemia protein in nuclear dots, and the SOX13 nuclear transcription factor. The relevance of these autoantibodies to immunopathogenesis is unknown.
Individual conditions grouped according to the international nosology and classification of genetic skeletal disorders*
Published in Christine M Hall, Amaka C Offiah, Francesca Forzano, Mario Lituania, Michelle Fink, Deborah Krakow, Fetal and Perinatal Skeletal Dysplasias, 2012
Christine M Hall, Amaka C Offiah, Francesca Forzano, Mario Lituania, Michelle Fink, Deborah Krakow
Genetics: an autosomal recessive condition caused by mutations in the lamin B receptor (LBR), an inner nuclear membrane protein. LBR is involved in two different processes: preservation of the chromatin structure, by promoting heterochromatin binding to the inner nuclear membrane, and cholesterol biosynthesis, by operating as sterol delta (14)-reductase. Heterozygous mutations in LBR cause Pelger-Huët anomaly (PHA), in which granulocytes show hypolobulated nuclei and abnormal chromatin structure. A specific genotype-phenotype correlation has been demonstrated, so that combined heterozygosity can result either in Greenberg dysplasia or in a different and much milder phenotype.
Pseudo Pelger-Huët anomalies as potential biomarkers for acute exposure radiation dose in rhesus macaques (Macaca mulatta)
Published in International Journal of Radiation Biology, 2022
Joshua M. Hayes, John D. Olson, Yuiko Chino, J. Daniel Bourland, J. Mark Cline, Thomas E. Johnson
There is a distinction between the Pelger-Huët Anomaly (PHA) and the pseudo Pelger-Huët anomaly (PPHA); PHAs are naturally occurring while PPHAs are induced morphologies. PHAs were first described in 1928 by the German physician, Karl Pelger, and were believed to be a sign of poor prognosis for tuberculosis (Pelger 1928). However, in 1932 G.J Huët discovered PHAs were linked to an autosomal dominant mutation on the long arm of chromosome 1 (Huët 1931). The mutation was in a gene that encodes for the lamin-B receptor, which is a membrane-associated protein embedded in the inner nuclear membrane of the nuclear envelope. The lamin-B receptor has two functions that can be described by its location on the protein. The carboxyl terminus performs C14 sterol reductase activity which involves the breaking of carbon double bonds in cholesterol synthesis, while the amine terminus of the lamin-B receptor binds to an intermediate filament called lamin-B. Lamin-B in turn binds to the chromatin and provides structure to both the chromatin and the nucleoplasm (Holmer et al. 1998). The structure of the nucleus is incredibly important to granulocytes because a hyper-segmented nucleus makes it much easier for these cells to exit the blood vascular compartment via diapedesis. The structure of the nucleus also allows for ease in movement throughout tissues as the cell is migrating to areas undergoing the inflammation response (Colella and Hollensead 2012). An image of the lamin-B receptor with the sterol reductase carboxyl terminus and the chromatin tethering amino terminus can be seen in Figure 1.