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101.
Jung-Chin Chang Simei Go Arthur J. Verhoeven Ulrich Beuers Ronald P.J. Oude Elferink 《生物化学与生物物理学报:疾病的分子基础》2018,1864(4):1232-1239
Primary biliary cholangitis (PBC) is a chronic fibrosing cholangiopathy characterized by an autoimmune stereotype and defective biliary bicarbonate secretion due to down-regulation of anion exchanger 2 (AE2). Despite the autoimmune features, immunosuppressants are ineffective while two bile acid-based therapies (ursodeoxycholic acid and obeticholic acid) have been shown to improve biochemical and histological features of cholestasis and long-term prognosis. However, the etiology and pathogenesis of PBC is largely unknown. Recently, it has been shown that microRNA-506 (miR-506) on chromosome X is up-regulated in PBC cholangiocytes and suppresses AE2 expression, which sensitizes cholangiocytes to bile salt-induced apoptosis by activating soluble adenylyl cyclase (sAC), an evolutionarily conserved bicarbonate sensor. In this review, we discuss the experimental evidence for the emerging role of the miR-506-AE2-sAC axis in PBC pathogenesis. We further hypothesize that the initial disease trigger induces an X-linked epigenetic change, leading to a female-biased activation of the miR-506-AE2-sAC axis. This article is part of a Special Issue entitled: Cholangiocytes in Health and Diseaseedited by Jesus Banales, Marco Marzioni and Peter Jansen. 相似文献
102.
Kothari S. Cavender-Bares J. Bitan K. Verhoeven A. S. Wang R. Montgomery R. A. Gamon J. A. 《Photosynthetica》2018,56(1):455-467
Photosynthetica - Photoprotective pigments, like those involved in the xanthophyll cycle, help plants avoid oxidative damage caused by excess radiation. This study aims to characterize a spectrum... 相似文献
103.
Increased transgenerational epigenetic variation,but not predictable epigenetic variants,after environmental exposure in two apomictic dandelion lineages 下载免费PDF全文
Veronica Preite Carla Oplaat Arjen Biere Jan Kirschner Wim H. van der Putten Koen J. F. Verhoeven 《Ecology and evolution》2018,8(5):3047-3059
DNA methylation is one of the mechanisms underlying epigenetic modifications. DNA methylations can be environmentally induced and such induced modifications can at times be transmitted to successive generations. However, it remains speculative how common such environmentally induced transgenerational DNA methylation changes are and if they persist for more than one offspring generation. We exposed multiple accessions of two different apomictic dandelion lineages of the Taraxacum officinale group (Taraxacum alatum and T. hemicyclum) to drought and salicylic acid (SA) treatment. Using methylation‐sensitive amplified fragment length polymorphism markers (MS‐AFLPs) we screened anonymous methylation changes at CCGG restriction sites throughout the genome after stress treatments and assessed the heritability of induced changes for two subsequent unexposed offspring generations. Irrespective of the initial stress treatment, a clear buildup of heritable DNA methylation variation was observed across three generations, indicating a considerable background rate of heritable epimutations. Less evidence was detected for environmental effects. Drought stress showed some evidence for accession‐specific methylation changes, but only in the exposed generation and not in their offspring. By contrast, SA treatment caused an increased rate of methylation change in offspring of treated plants. These changes were seemingly undirected resulting in increased transgenerational epigenetic variation between offspring individuals, but not in predictable epigenetic variants. While the functional consequences of these MS‐AFLP‐detected DNA methylation changes remain to be demonstrated, our study shows that (1) stress‐induced transgenerational DNA methylation modification in dandelions is genotype and context‐specific; and (2) inherited environmental DNA methylation effects are mostly undirected and not targeted to specific loci. 相似文献
104.
Computer-Assisted Identification of Protoplasts Responsible for Rare Division Events Reveals Guard-Cell Totipotency 总被引:3,自引:2,他引:1 下载免费PDF全文
With the use of a computer-controlled microscope system to assist in the positioning and rapid relocation of large numbers of cultured cells, we were able to identify those protoplasts with the capacity to divide within a highly recalcitrant culture in which only a tiny fraction of the total population proceeds to produce viable microcalli. In the cultures used, comprising Beta vulgaris L. (sugar beet) leaf protoplasts, it was confirmed that these cells can be recognized solely on the basis of morphological characters. Therefore, a direct link exists between competence for cell division in vitro and cell type. Divergent callus morphologies and totipotent potential could also be ascribed to distinct protoplast types and hence to cells with a specific origin. The progenitors of the totipotent protoplasts in these cultures have been confirmed as being stomatal guard cells. Consequently, in plants even the most highly adapted living cells clearly retain and can reactivate all of the functional genetic information necessary to recreate the whole organism; an extreme degree of cytodifferentiation is, therefore, no hindrance to expressing totipotent potential. In addition to the considerable practical value of these findings, their implications concerning our understanding of both the control of gene expression and plant cell differentiation and its reversibility are of fundamental significance. 相似文献
105.
Summary Data on isolation, purification and transfer of mitochondria from a cytoplasmic male sterile line of the Ogura type of Raphanus sativus to a male fertile line of Brassica napus are reported. Microinjection has been used for the transfer of the donor mitochondria to the recipient protoplasts. The injected protoplasts were identified and followed individually throughout their development using a computerized microscope stage which greatly enhanced the number of injections (five-fold). The transferred donor mitochondria were stably maintained during several successive cell divisions, revealing that they were viable and functional. Several calluses were obtained from injected protoplasts without using any selection pressure. Restriction fragment length analysis of seventeen calluses, using mitochondrial DNA probes, indicated that three contained the donor Ogura type mitochondria. No recombinant types of mitochondria have been observed. Flow cytometric and karyotype analyses of the calluses revealed the presence of similar amount of DNA and chromosome number as those of the recipient plants of B.napus. The application of microinjection for the manipulation of cytoplasmic composition is discussed.Abbreviations ATPase
adenosine triphosphate phosphohydrolase
- BSA
bovine serum albumin
- CMS
cytoplasmic male sterility
- DIOC6(3)
3,3-dihexyloxacarbocyanine-iodide
- mt
mitochondria(I)
- PEG
polyethylene glycol
- RFLP
restriction fragment length polymorphism
- UV
ultraviolet 相似文献
106.
A gene for autosomal dominant nonsyndromic hearing loss (DFNA12) maps to chromosome 11q22-24. 总被引:1,自引:1,他引:0 下载免费PDF全文
K Verhoeven G Van Camp P J Govaerts W Balemans I Schatteman M Verstreken L Van Laer R J Smith M R Brown P H Van de Heyning T Somers F E Offeciers P J Willems 《American journal of human genetics》1997,60(5):1168-1173
We performed linkage analysis in a Belgian family with autosomal dominant midfrequency hearing loss, which has a prelingual onset and a nonprogressive course in most patients. We found LOD scores >6 with markers on chromosome 11q. Analysis of key recombinants maps this deafness gene (DFNA12) to a 36-cM interval on chromosome 11q22-24, between markers D11S4120 and D11S912. The critical regions for the recessive deafness locus DFNB2 and the dominant locus DFNA11, which were previously localized to the long arm of chromosome 11, do not overlap with the candidate interval of DFNA12. 相似文献
107.
E. Rutgers K. S. Ramulu P. Dijkhuis J. Blaas F. A. Krens H. A. Verhoeven 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,94(8):1053-1059
Results are reported on the integration sites and copy number of alien marker genes neomycin phosphotransferase II (nptII) and β-glucuronidase (uidA), introduced into diploid potato Solanum tuberosum through transformation by Agrobacterium tumefaciens. Also, the transgenic potato chromosomes 3 and 5 harbouring the nptII and uidA genes, which were transferred to tomato (wild species Lycopersicon peruvianum) by microprotoplast fusion, as revealed by genomic in situ hybridization (GISH), were identified by RFLP analysis using chromosome-specific
markers. The data revealed three integration sites in the donor potato genome, each containing the uidA gene, and two also harbouring the nptII gene. Analysis of monosomic-addition hybrid plants obtained after microprotoplast fusion showed that each of these three
integration sites is located on a different potato chromosome. The microprotoplast hybrid plants contained only the chromosomes
that carried the selectable gene nptII. The data on sexual transmission of the donor potato chromosome carrying the uidA and nptII genes were obtained by analysing the first backcross progeny (BC1) derived from crossing a monosomic-addition hybrid plant to tomato (L. peruvianum). The glucuronidase (GUS) assay and PCR analysis using primers for the uidA gene indicated the presence of the potato chromosome in GUS-positive and its absence in GUS-negative BC1 plants. RFLP analysis confirmed sexual transmission of the potato chromosome carrying the nptII and uidA genes to the BC1 plants. A few BC1 plants contained the nptII and uidA genes in the absence of the potato additional chromosome, indicating that the marker genes were integrated into the tomato
genome. The potential applications of the transfer of alien chromosomes and genes by microprotoplast fusion technique are
discussed.
Recieved: 1 September 1996 / Accepted: 20 September 1996 相似文献
108.
Lihua Shen Kristien Van Dyck Joop Luten Hendrik Deelstra 《Biological trace element research》1997,58(1-2):55-63
The present study was undertaken to evaluate the in vitro availability of chemically varying forms of selenium (Se), supplemented in cow's milk. Two inorganic (selenite and selenate) and two organic (seleno-methionine [Se-Met] and seleno-cystine [Se-Cys]) Se sources were evaluated. The in vitro availability was estimated by the diffusibility of Se during simulated gastrointestinal digestion. First, the diffusibility was compared after adding a constant amount of Se as either selenate, selenite, seleno-methionine, or Se-Cys in milk samples. Se-Met and selenate were found to be significantly more diffusible than selenocystine and selenite under the simulated gastrointestinal conditions. The tendency for superior in vitro availability of selenate and Se-Met compared to selenite and Se-Cys was confirmed for a supplementation range of 5–40 ng/g of Se. This study suggests that the high diffusibility of selenate and Se-Met in a simulated gastrointestinal environment may contribute to their high absorption in vivo. 相似文献
109.
Futoshi Kuribayashi Martin de Boer Jeanette H. W. Leusen Arthur J. Verhoeven Dirk Roos 《Human genetics》1996,97(5):611-613
We have identified a rare polymorphism (G to C at nucleotide 1102) in CYBB, which codes for gp91-phox, a component of NADPH oxidase. Polymorphonuclear leukocytes with this enzyme produced normal amounts of superoxide anion.
Received: 28 August 1995 相似文献
110.
Geoffrey?OmuseEmail author Kristien?Nel?Van?Zyl Kim?Hoek Shima?Abdulgader Samuel?Kariuki Andrew?Whitelaw Gunturu?Revathi 《Annals of clinical microbiology and antimicrobials》2016,15(1):51