Search results for "imprint"

Sequence-based bioinformatic prediction and QUASEP identify genomic imprinting of the KCNK9 potassium channel gene in mouse and human

2007

Genomic imprinting is the epigenetic marking of gene subsets resulting in monoallelic or predominant expression of one of the two parental alleles according to their parental origin. We describe the systematic experimental verification of a prioritized 16 candidate imprinted gene set predicted by sequence-based bioinformatic analyses. We used Quantification of Allele-Specific Expression by Pyrosequencing (QUASEP) and discovered maternal-specific imprinted expression of the Kcnk9 gene as well as strain-dependent preferential expression of the Rarres1 gene in E11.5 (C57BL/6 3 Cast/Ei)F1 and informative (C57BL/6 3 Cast/ Ei) 3 C57BL/6 backcross mouse embryos. For the remaining 14 candidate impr…

The Gpr1/Zdbf2 locus provides new paradigms for transient and dynamic genomic imprinting in mammals

2014

Many loci maintain parent-of-origin DNA methylation only briefly after fertilization during mammalian development: Whether this form of transient genomic imprinting can impact the early embryonic transcriptome or even have life-long consequences on genome regulation and possibly phenotypes is currently unknown. Here, we report a maternal germline differentially methylated region (DMR) at the mouse Gpr1/Zdbf2 (DBF-type zinc finger-containing protein 2) locus, which controls the paternal-specific expression of long isoforms of Zdbf2 (Liz) in the early embryo. This DMR loses parental specificity by gain of DNA methylation at implantation in the embryo but is maintained in extraembryonic tissue…

Tracking paternal genes with DALP markers in a pseudoarrhenotokous reproductive system: biparental transmission but haplodiploid-like inheritance in …

2000

International audience; The complexity of some sexual reproductive systems in arthropods still leaves both their genetic and epigenetic determinism and their evolutionary significance poorly understood. Pseudoarrhenotoky is characterized by obligate fertilization and differential inactivation and/or elimination of paternal chromosomes in embryos that develop into males. Here, we investigate how the paternal genome is transmitted in a pseudoarrhenotokous mite, Neoseiulus californicus, using codominant genetic markers detected by DALP (direct amplification of length polymorphism). Transmission patterns of parental alleles through one and two generations are reported at four or five loci corre…

Duchenne muscular dystrophy and idiopathic hyperCKemia segregating in a family

1995

A 7-month-old boy with gross motor delay and failure to thrive presented with rhabdomyolysis following an acute asthmatic episode. During hospitalization an electrocardiographic conversion to a Wolff-Parkinson-White type 1 (WPW) pattern took place. Duchenne muscular dystrophy (DMD) was suspected based on elevated creatine kinase (CK) serum levels, muscle biopsy, and family history. The diagnosis was confirmed by molecular analysis, which documented a deletion corresponding to cDNA probe 1-2a in the dystrophin gene, in the propositus and in an affected male cousin of his mother. "Idiopathic" hyperCKemia was found in the propositus, his father, and 5 of his relatives. We suggest that the unus…

Innovations in Extractive Phases for In-Tube Solid-Phase Microextraction Coupled to Miniaturized Liquid Chromatography: A Critical Review

2020

Over the past years, a great effort has been devoted to the development of new sorbents that can be used to pack or to coat extractive capillaries for in-tube solid-phase microextraction (IT-SPME). Many of those efforts have been focused on the preparation of capillaries for miniaturized liquid chromatography (LC) due to the reduced availability of capillary columns with appropriate dimensions for this kind of system. Moreover, many of the extractive capillaries that have been used for IT-SPME so far are segments of open columns from the gas chromatography (GC) field, but the phase nature and dimensions are very limited. In particular, polar compounds barely interact with stationary GC phas…

Layer-by-Layer Grafting of Molecularly Imprinted Polymers via Iniferter Modified Supports

2002

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…

Smart Sorption Materials in Green Analytical Chemistry

2019

The use of smart materials as alternative sorption materials for their use in greening sample preparation has been reviewed. It has been taking into consideration recent advances on the use of natural products, without any modification or purification, for making analyte extraction and pre-concentration and the use of specific materials in solid-phase extraction (SPE) and solid-phase microextraction (SPME) approaches. Inorganic materials, such as metal oxides, alumina-based, silica-based, and carbon-based materials together with biomimetic sorbents such as classical immunosorbents, aptamers, and molecularly imprinted polymers, have been reviewed as examples of these materials, stressing the…

Evaluation of a Multidimensional Solid-Phase Extraction Platform for Highly Selective On-Line Cleanup and High-Throughput LC−MS Analysis of Triazines…

2001

A novel highly selective sample cleanup procedure based on the use of molecularly imprinted polymers (MIPs) as solid-phase extraction materials has been evaluated with respect to its applicability and routine use in environmental analysis. The method comprises the combination of a restricted access material (RAM) and a MIP allowing a selective sample preparation to be achieved in the online mode. This combination is called the size-selective sample separation and solvent switch (six-SPE). The RAM column combines size exclusion and adsorption chromatography, reducing the concentration of matrix molecules by a cutoff of 15 kDa. The MIP column selectively retains the triazine analytes whereas …

Selective trace enrichment of chlorotriazine pesticides from natural waters and sediment samples using terbuthylazine molecularly imprinted polymers

2000

Two molecularly imprinted polymers were synthesized using either dichloromethane or toluene as the porogen and terbuthylazine as the template and were used as solid-phase extraction cartridges for the enrichment of six chlorotriazines (deisopropylatrazine, deethylatrazine, simazine, atrazine, propazine, and terbuthylazine) in natural water and sediment samples. The extracted samples were analyzed by liquid chromatography/diode array detection (LC/DAD). Several washing solvents, as well as different volumes, were tested for their ability to remove the matrix components nonspecifically adsorbed on the sorbents. This cleanup step was shown to be of prime importance to the successful extraction…