Search results for " nucleic acid"
showing 10 items of 272 documents
X-ray structures of five variably tert-butoxycarbonyl-substituted adenines and their liquid and solid state NMR investigations
2009
Abstract Adenine reacts selectively with di- tert -butyldicarbonate in THF in the presence of NaOH to give N 9-monoBoc-adenine 1 . The molecular structure and crystal packing of this and four other variably substituted Boc-derivatives of adenine were determined in solid state by means of X-ray diffraction and CP/MAS NMR experiments and characterized in liquid state by 1 H, 13 C, and 15 N NMR spectroscopy as well. Additionally, crystal structure of inclusion compound between N 6 -monoBoc-adenine 5 and CHCl 3 is reported. Tautomeric equilibria of mono- and disubstituted derivatives 4 and 5 in liquid state were studied by VT NMR experiments.
3-Diazopyrroles—IV. Structure determination using 13C NMR spectroscopy
1990
Abstract On the basis of the 13 C NMR chemical shifts, it is proposed that, although b is the major canonical structure, structure c , in which a negative charge resides at C-3, provides an important contribution to the resonance stabilization of the 3-diazopyrroles, 1–4 .
Intracerebral Borna Disease Virus Infection of Bank Voles Leading to Peripheral Spread and Reverse Transcription of Viral RNA
2011
Bornaviruses, which chronically infect many species, can cause severe neurological diseases in some animal species; their association with human neuropsychiatric disorders is, however, debatable. The epidemiology of Borna disease virus (BDV), as for other members of the family Bornaviridae, is largely unknown, although evidence exists for a reservoir in small mammals, for example bank voles (Myodes glareolus). In addition to the current exogenous infections and despite the fact that bornaviruses have an RNA genome, bornavirus sequences integrated into the genomes of several vertebrates millions of years ago. Our hypothesis is that the bank vole, a common wild rodent species in traditional B…
Neuronal precursor-specific activity of a human doublecortin regulatory sequence.
2005
The doublecortin (DCX) gene encodes a 40-kDa microtubule-associated protein specifically expressed in neuronal precursors of the developing and adult CNS. Due to its specific expression pattern, attention was drawn to DCX as a marker for neuronal precursors and neurogenesis, thereby underscoring the importance of its promoter identification and promoter analysis. Here, we analysed the human DCX regulatory sequence and confined it to a 3.5-kb fragment upstream of the ATG start codon. We demonstrate by transient transfection experiments that this fragment is sufficient and specific to drive expression of reporter genes in embryonic and adult neuronal precursors. The activity of this regulator…
Unraveling the interaction between doxorubicin and DNA origami nanostructures for customizable chemotherapeutic drug release
2021
We thank Dr H. Häkkänen for technical assistance and S. Julin for the 24HB DNA origami design. We acknowledge the provision of facilities and technical support by Aalto University Bioeconomy Facilities and OtaNano – Nanomicroscopy Center (Aalto-NMC). The research was carried out under the Academy of Finland Centres of Excellence Programme (2014–2019). Academy of Finland [308578 to M.A.K.]; Deutsche Forschungsgemeinschaft [Emmy Noether Programme to A.H.-J., SFB1032 (Project A06) to T.L.]; Emil Aaltonen Foundation [to H.I. and V.L.]; Jane and Aatos Erkko Foundation [to J.A.I. and V.L.]; Sigrid Jusélius Foundation [to V.L.]; Vilho, Yrjö and Kalle Väisälä Foundation of the Finnish Academy of Sc…
CYP3 phylogenomics: evidence for positive selection of CYP3A4 and CYP3A7.
2008
CYP3A metabolizes 50% of currently prescribed drugs and is frequently involved in clinically relevant drug interactions. The understanding of roles and regulations of the individual CYP3A genes in pharmacology and physiology is incomplete.Using genomic sequences from 16 species we investigated the evolution of CYP3 genomic loci over a period of 450 million years.CYP3A genes in amniota evolved from two ancestral CYP3A genes. Upon the emergence of eutherian mammals, one of them was lost, whereas, the other acquired a novel genomic environment owing to translocation. In primates, CYP3A underwent rapid evolutionary changes involving multiple gene duplications, deletions, pseudogenizations, and …
Identification of protein IT of the intestinal cytoskeleton as a novel type I cytokeratin with unusual properties and expression patterns.
1990
A major cytoskeletal polypeptide (Mr approximately 46,000; protein IT) of human intestinal epithelium was characterized by biochemical and immunological methods. The polypeptide, which was identified as a specific and genuine mRNA product by translation in vitro, reacted, in immunoblotting after SDS-PAGE, only with one of numerous cytokeratin (CK) antisera tested but with none of many monoclonal CK antibodies. In vitro, it formed heterotypic complexes with the type II CK 8, as shown by blot binding assays and gel electrophoresis in 4 M urea, and these complexes assembled into intermediate filaments (IFs) under appropriate conditions. A chymotrypsin-resistant Mr approximately 38,000 core fra…
Reciprocal regulation of the human sterol regulatory element binding protein (SREBP)-1a promoter by Sp1 and EGR-1 transcription factors.
2007
AbstractSterol regulatory element binding protein (SREBP)-1a is a transcription factor that is highly expressed in actively growing cells, and is involved in the biosynthesis of cholesterol, fatty acids and phospholipids. We have mapped the minimal human SREBP-1a promoter region to 75bp upstream of the translation start site where we discovered a functional role for the 3 GC-boxes containing overlapping sites for the Sp1 and EGR-1 transcription factors. Intact SP1-binding sites are essential for promoter activity, whereas EGR-1 suppresses the transcription of the human SREBP-1a promoter. These results reveal a novel physiologically relevant transcriptional mechanism for the reciprocal regul…
Multiple copies of SUC4 regulatory regions may cause partial de-repression of invertase synthesis in Saccharomyces cerevisiae.
1992
Transformation to generate multiple copies of regulatory DNA sequences has been used to study the interactions between regulatory proteins and their target sequences, since a high copy number of these sequences may titrate trans-acting regulatory proteins. We have analyzed the synthesis of invertase in yeast strains carrying different SUC genes transformed with the multiple-copy plasmid pSH143, a derivative of pJDB207 containing the promoter and upstream regulatory sequences of SUC4. The results obtained seem to be strain dependent. Under repressing conditions a high copy number of SUC4 promoter regions may cause increased expression of the invertase genes resulting in the synthesis of exte…
Dielectrophoretic trapping of multilayer DNA origami nanostructures and DNA origami-induced local destruction of silicon dioxide
2015
DNA origami is a widely used method for fabrication of custom-shaped nanostructures. However, to utilize such structures, one needs to controllably position them on nanoscale. Here we demonstrate how different types of 3D scaffolded multilayer origamis can be accurately anchored to lithographically fabricated nanoelectrodes on a silicon dioxide substrate by DEP. Straight brick-like origami structures, constructed both in square (SQL) and honeycomb lattices, as well as curved "C"-shaped and angular "L"-shaped origamis were trapped with nanoscale precision and single-structure accuracy. We show that the positioning and immobilization of all these structures can be realized with or without thi…