Search results for " Northern"
showing 10 items of 216 documents
Bio-sintering processes in hexactinellid sponges: Fusion of bio-silica in giant basal spicules from Monorhaphis chuni☆
2009
The two sponge classes, Hexactinellida and Demospongiae, comprise a skeleton that is composed of siliceous skeletal elements (spicules). Spicule growth proceeds by appositional layering of lamellae that consist of silica nanoparticles, which are synthesized via the sponge-specific enzyme silicatein. While in demosponges during maturation the lamellae consolidate to a solid rod, the lamellar organization of hexactinellid spicules largely persists. However, the innermost lamellae, near the spicule core, can also fuse to a solid axial cylinder. Similar to the fusion of siliceous nanoparticles and lamella, in several hexactinellid species individual spicules unify during sintering-like processe…
Expression of synapsin I gene in primary cultures of differentiating rat cortical neurons
1995
Synapsin I is a neuron-specific protein which is present in two isoforms, Ia and Ib. In the last few years this protein has been demonstrated to play a central role in the regulation of neurotransmitter release and synaptic plasticity. In this paper the developmental expression of this protein has been investigated in primary neuronal cultures from fetal rat brain cortices. The presence of thyroid hormone in the culture medium stimulates an early expression of the protein without exerting any effect at the level of mRNA transcription and accumulation. These observations implicate a T3-dependent regulation of this neuron-specific gene at the level of mRNA translation. © 1995 Plenum Publishin…
Expression of retinoic acid nuclear receptors in the mouse embryonal carcinoma cell line PCC7-Mz1
1992
Mouse embryonal carcinoma cell line PCC7-Mz1 can serve as a model of mammalian neural development [1989, J. Cell. Biol. 109, 2481-2493]. Upon exposure to all-trans retinoic acid (RA), Mz1 cells differentiate into a stable pattern of neurons, astroglia and fibroblasts whereas variants of the parental cell line either are restricted in their patterns of derivatives or do not respond at all to RA. Using gene probes specific for the alpha 1, alpha 2 and beta 2 isoforms of the retinoic acid nuclear receptor, we have studied by Northern blot analysis the expression of these transcription factors in uninduced and induced cells of clone Mz1 and in variants with different developmental potential. al…
Fine mapping of the 2p11 dyslexia locus and exclusion of TACR1 as a candidate gene.
2003
Developmental dyslexia, or reading disability, is a multigenic complex disease for which at least five loci, i.e. DYX1-3 and DYX5-6, have been clearly identified from the human genome. To date, DYX1C1 is the only dyslexia candidate gene cloned. We have previously reported linkage to 2p11 and 7q32 in 11 Finnish pedigrees. Here, we report the fine mapping of the approximately 40-cM linked region from chromosome 2 as we increased marker density to one per 1.8 cM. Linkage was supported with the highest NPL score of 3.0 (P=0.001) for marker D2S2216. Association analysis using the six pedigrees showing linkage pointed to marker D2S286/rs3220265 (P value0.001) in the near vicinity of D2S2216. We w…
Autosomal dominant polycystic kidney disease—in vitro culture of cyst-lining epithelial cells
1992
The major form of autosomal dominant polycystic kidney disease (ADPKD) in humans is linked to the PKD1 gene on chromosome 16p. The identity of the gene and the underlying pathogenetic mechanisms are not yet defined. Cyst-lining epithelial cells derived from a polycystic kidney were successfully grown in culture and designated MZ-PKD-1 cells. By linkage analysis, the related pedigree of the nephrectomized patient could be linked to the PKD1 gene on chromosome 16p. Thus, these cells exhibit the genotype of a mutated PKD1 gene and represent an in vitro culture model for ADPKD involving chromosome 16p. The antigenic phenotype was characterized immunohistologically by epithelial differentiation …
Impairment of TGF-β signaling in T cells increases susceptibility to experimental autoimmune hepatitis in mice
2002
In autoimmune hepatitis, strong TGF-beta1 expression is found in the inflamed liver. TGF-beta overexpression may be part of a regulatory immune response attempting to suppress autoreactive T cells. To test this hypothesis, we determined whether impairment of TGF-beta signaling in T cells leads to increased susceptibility to experimental autoimmune hepatitis (EAH). Transgenic mice of strain FVB/N were generated expressing a dominant-negative TGF-beta type II receptor in T cells under the control of the human CD2 promoter/locus control region. On induction of EAH, transgenic mice showed markedly increased portal and periportal leukocytic infiltrations with hepatocellular necroses compared wit…
A new method for the mapping of 5' ends of RNAs.
2008
In this article, we describe a new procedure to map 5' ends of RNAs. The procedure consists in the use of specific RNase H digestion of a hybrid formed by the RNA and a complementary DNA oligonucleotide. Northern blot hybridization of the resulting RNA fragment allows an accurate measurement of its length. Although we generally use this procedure as a control of previously performed primer extension analyses, the absence of nonspecific bands, which often occur in primer extensions on RNA templates with extended secondary structures, suggests that our method may be preferable when these difficult templates are analyzed.
Genome-wide scan for selection signatures reveals novel insights into the adaptive capacity in local North African cattle
2020
International audience; Natural-driven selection is supposed to have left detectable signatures on the genome of North African cattle which are often characterized by the fixation of genetic variants associated with traits under selection pressure and/or an outstanding genetic differentiation with other populations at particular loci. Here, we investigate the population genetic structure and we provide a first outline of potential selection signatures in North African cattle using single nucleotide polymorphism genotyping data. After comparing our data to African, European and indicine cattle populations, we identified 36 genomic regions using three extended haplotype homozygosity statistic…
Genotypic analysis at multiple loci across Kaposi's sarcoma herpesvirus (KSHV) DNA molecules: clustering patterns, novel variants and chimerism
2001
Abstract Background: the genomes of human Kaposi's sarcoma-associated herpesvirus (KSHV) display several levels of DNA sequence heterogeneity and subgrouping that show distinctive clustering patterns in related human populations. The four major subtype patterns for the hypervariable ORF-K1 protein correlate closely with the principal diasporas resulting from the migration of modern humans out of East Africa and suggest that KSHV is an ancient human virus that is transmitted primarily in a familial fashion with consequent very low recombination rates. However, chimeric genomes have also been detected, especially with regard to the presence of P versus M alleles of the ORF-K15 gene. Objective…
Sorbus madoniensis (Rosaceae), a new species from Sicily
2012
Abstract Sorbus madoniensis, a new species of Sorbus sect. Aria, is described, so far known only from two neighbouring localities on Mt. Carbonara (Madonie mountains, Sicily). It is related to S. graeca, which also occurs in the Madonie, and indeed shares with S. madoniensis one of its localities.