Search results for "Hybridization"

Imbibition of Femtoliter-Scale DNA-Rich Aqueous Droplets into Porous Nylon Substrates by Molecular Printing

2019

This work presents the first reported imbibition mechanism of femtoliter (fL)-scale droplets produced by microchannel cantilever spotting (μCS) of DNA molecular inks into porous substrates (hydrophilic nylon). Differently from macroscopic or picoliter droplets, the downscaling to the fL-size leads to an imbibition process controlled by the subtle interplay of evaporation, spreading, viscosity, and capillarity, with gravitational forces being quasi-negligible. In particular, the minimization of droplet evaporation, surface tension, and viscosity allows for a reproducible droplet imbibition process. The dwell time on the nylon surface permits further tuning of the droplet lateral size, in acc…

Relationships of the Woody Medicago Species (Section Dendrotelis) Assessed by Molecular Cytogenetic Analyses

2008

†Background and Aims The organization of rDNA genes in the woody medic species from the agronomically important Medicago section Dendrotelis was analysed to gain insight into their taxonomic relationships, to assess the levels of infraspecific variation concerning ribosomal loci in a restricted and fragmented insular species (M. citrina) and to assess the nature of its polyploidy. †Methods Fluorescence in situ hybridization (FISH) was used for physical mapping of 5S and 45S ribosomal DNA genes in the three species of section Dendrotelis (M. arborea, M. citrina, M. strasseri) and the related M. marina from section Medicago. Genomic in situ hybridization (GISH) was used to assess the genomic …

Chromosomal location polymorphism of major rDNA sites in two Mediterranean populations of the killifih Aphanius fasciatus (Pisces: Cyprinodontidae)

2005

The chromosomes of the Mediterranean killifish, Aphanius fasciatus from two populations, the Lagoon of Venice (LV, 15 specimens) and the Lagoon ‘Stagnone di Marsala’ (Sicily) (SM, 48 specimens), have been investigated using conventional Ag-staining and fluorescent in situ hybridization (FISH) with 18S rDNA probe. The two methods revealed variation in the number of major rDNA sites ranging from 8 to 14 (LV) and from 1 to 4 (SM) per individual. The fact that each individual possessed its own number of sites implies that observed variation was structural. Moreover, overlapping of silver staining and FISH patterns demonstrated that all ribosomal genes were transcriptionally active in each speci…

Individual variability of mytimycin gene expression in mussel

2012

The antifungal peptide mytimycin (MytM) is synthesized by hemocytes of the Mediterranean mussel, Mytilus galloprovincialis. In addition to sequence and gene structure diversities previously reported from pooled hemocytes, the present report focused on the expression of mytm gene in individual M. galloprovincialis, before and after challenge. Within untreated mussel, MytM mRNA was observed by ISH in about 42% of circulating hemocytes, characterized by large, diffuse nucleus. Injection with Fusarium oxysporum increased such percentage, but in only some of the mussels. Similarly, MytM gene expression increased after injection in only some of the mussels, as measured by qPCR. Responders and not…

Manganese interferes with calcium, perturbs ERK signaling, and produces embryos with no skeleton.

2011

Manganese (Mn) has been associated with embryo toxicity as it impairs differentiation of neural and skeletogenic cells in vertebrates. Nevertheless, information on the mechanisms operating at the cellular level remains scant. We took advantage of an amenable embryonic model to investigate the effects of Mn in biomineral formation. Sea urchin (Paracentrotus lividus) embryos were exposed to Mn from fertilization, harvested at different developmental stages, and analyzed for their content in calcium (Ca), expression of skeletogenic genes, localization of germ layer markers, and activation of the extracellular signal-regulated kinase (ERK). By optical and immunofluorescence microscopy, we found…

Expression and distribution of the glucocorticoid receptor DlGR1 in the teleost Dicentrarchus labrax brain

2009

Cortisol is the main corticosteroid secreted by the interrenal cells of the head kidney and it exerts a role in mantaining the omeostatic status in fish. In teleosts its effects are mediated through intracellular receptors expressed in several tissues, that are ligand-dependent transcription factors by binding to specific tissue DNA sequences. In Dicentrarchus labrax we previously cloned and sequenced a glucocorticoid receptor, DlGR1, isolated from leukocytes of peritoneal cavity. In this work we showed mRNA expression and tissue immunohistochemical localization of brain DlGR1 by in situ hybridization assays, with a riboprobe with DlGR1 cDNA trascriptional activation domain, and by immunohi…

Localization of cytokeratin 10 mRNA in human epidermis using nonradioactive in situ hybridization as a routine method

1998

Oligonucleotide probes detect splicing variants insituinDrosophilaembryos

1992

We describe a method for the in situ detection of specific splicing variants. The method is based on the use of antisense oligonucleotides designed to span splice junctions labelled with digoxigenin by terminal transferase tailing. We find that the spatial patterns of Ubx splicing variants Ia and IIa are similar in early embryos, but differ in late embryos. Variant IVa is only detected in the CNS (ps6) at stages 16 and 17. We also present evidence indicating that the first splicing event is cotranscriptional.

Localization and mRNA steady-state level of cellular fibronectin in rat liver undergoing a CCl4-induced acute damage or fibrosis.

1993

Abstract In an attempt to investigate cellular fibronectin synthesis and deposition during acute liver damage and fibrogenesis, we used the presence of the additional type III-related ED-A domain of cellular fibronectin as a characteristic for distinguishing it from the plasma form. Using site-specific antibodies, we localized cellular fibronectin deposition in the necrotic pericentral areas of acutely damaged liver tissue after a single CCl 4 -gavage, whereas in control liver only trace amounts of cellular fibronectin were detectable along the sinusoids. Upon several CCl 4 -administrations leading to liver fibrosis, cellular fibronectin deposits were accumulated in the fibrotic septa. Nort…

Group-specific quantification of methanotrophs in landfill gas-purged laboratory biofilters by tyramide signal amplification-fluorescence in situ hyb…

2008

The aim of this study was to quantitatively analyse methanotrophs in two laboratory landfill biofilters at different biofilter depths and at temperatures which mimicked the boreal climatic conditions. Both biofilters were dominated by type I methanotrophs. The biofilter depth profiles showed that type I methanotrophs occurred in the upper layer, where relatively high O(2) and low CH(4) concentrations were present, whereas type II methanotrophs were mostly distributed in the zone with high CH(4) and low O(2) concentrations. The number of type I methanotrophic cells declined when the temperature was raised from 15 degrees C to 23 degrees C, but increased when lowered to 5 degrees C. A slight …