Features of medullary thymic epithelium implicate postnatal development in maintaining epithelial heterogeneity and tissue-restricted antigen expression.
AuthorsGillard GO, Farr AG
JournalJ Immunol
PubMed ID16670287
'Although putative thymic epithelial progenitor cells have been identified, the developmental potential of these cells, the extent of medullary thymic epithelium (mTEC) heterogeneity, and the mechanisms that mediate the expression of a wide range of peripheral tissue-restricted Ags (TRAs) by mTECs remain poorly defined. Here we have defined several basic ... More
Biotinylated photocleavable polyethylenimine: capture and triggered release of nucleic acids from solid supports.
AuthorsHandwerger RG, Diamond SL
JournalBioconjug Chem
PubMed ID17432825
'A biotinylated photocleavable polyethylenimine (B-PC-PEI) was designed and synthesized for the capture and controlled release of nucleic acids from solid supports. B-PC-PEI was synthesized via a three-step reaction process and verified by 1H NMR and mass spectrometry. In aqueous solution, the o-nitrobenzyl group within B-PC-PEI was efficiently cleaved by 5 ... More
Development of a SYBR safe technique for the sensitive detection of DNA in cesium chloride density gradients for stable isotope probing assays.
AuthorsMartineau C, Whyte LG, Greer CW,
JournalJ Microbiol Methods
PubMed ID18329741
SYBR safe, a fluorescent nucleic acid stain, was evaluated as a replacement for ethidium bromide (EtBr) in cesium chloride (CsCl) density gradients for DNA stable isotope probing (DNA-SIP) assays. The separation of 12C- and 13C-labelled DNA using SYBR safe gave similar results to those obtained using EtBr with pure cultures ... More
Single step protocol to purify recombinant proteins with low endotoxin contents.
AuthorsReichelt P, Schwarz C, Donzeau M
JournalProtein Expr Purif
PubMed ID16290005
Endotoxin is an unwanted by product of recombinant proteins purified from Escherichia coli. The inherent toxicity of endotoxins makes their removal an important step for the proteins' application in several biological assays and for safe parenteral administration. The method described in this paper is a one-step protocol which is effective ... More
5-Methyltetrahydrofolate inhibits photosensitization reactions and strand breaks in DNA.
AuthorsOffer T, Ames BN, Bailey SW, Sabens EA, Nozawa M, Ayling JE
JournalFASEB J
PubMed ID17341682
The known functions of folate are to support one-carbon metabolism and to serve as photoreceptors for cryptochromes and photolyases. We demonstrate that 5-methyltetrahydrofolate (5-MTHF, the predominant folate in plasma) is also a potent, near diffusion limited, scavenger of singlet oxygen and quencher of excited photosensitizers. Both pathways result in decomposition ... More
Mechanisms of palatal epithelial seam disintegration by transforming growth factor (TGF) beta3.
AuthorsAhmed S, Liu CC, Nawshad A,
JournalDev Biol
PubMed ID17698055
TGFbeta3 signaling initiates and completes sequential phases of cellular differentiation that is required for complete disintegration of the palatal medial edge seam, that progresses between 14 and 17 embryonic days in the murine system, which is necessary in establishing confluence of the palatal stroma. Understanding the cellular mechanism of palatal ... More
High-density yeast-tiling array reveals previously undiscovered introns and extensive regulation of meiotic splicing.
AuthorsJuneau K, Palm C, Miranda M, Davis RW
JournalProc Natl Acad Sci U S A
PubMed ID17244705
Knowing gene structure is vital to understanding gene function, and accurate genome annotation is essential for understanding cellular function. To this end, we have developed a genome-wide assay for mapping introns in Saccharomyces cerevisiae. Using high-density tiling arrays, we compared wild-type yeast to a mutant deficient for intron degradation. Our ... More
Combinatorial Domain Hunting: An effective approach for the identification of soluble protein domains adaptable to high-throughput applications.
AuthorsReich S, Puckey LH, Cheetham CL, Harris R, Ali AA, Bhattacharyya U, Maclagan K, Powell KA, Prodromou C, Pearl LH, Driscoll PC, Savva R
JournalProtein Sci
PubMed ID17008718
Exploitation of potential new targets for drug and vaccine development has an absolute requirement for multimilligram quantities of soluble protein. While recombinant expression of full-length proteins is frequently problematic, high-yield soluble expression of functional subconstructs is an effective alternative, so long as appropriate termini can be identified. Bioinformatics localizes domains, ... More
A mutant alphaII-spectrin designed to resist calpain and caspase cleavage questions the functional importance of this process in vivo.
AuthorsMeary F, Metral S, Ferreira C, Eladari D, Colin Y, Lecomte MC, Nicolas G
JournalJ Biol Chem
PubMed ID17374614
alpha- and beta-spectrins are components of molecular scaffolds located under the lipid bilayer and named membrane skeletons. Disruption of these scaffolds through mutations in spectrins demonstrated that they are involved in the membrane localization or the maintenance of proteins associated with them. The ubiquitous alphaII-spectrin chain bears in its central ... More
Switch from caspase-dependent to caspase-independent death during heart development: essential role of endonuclease G in ischemia-induced DNA processing of differentiated cardiomyocytes.
AuthorsBahi N, Zhang J, Llovera M, Ballester M, Comella JX, Sanchis D
JournalJ Biol Chem
PubMed ID16754658
Differentiated cardiomyocytes are resistant to caspase-dependent cell death; however, the mechanisms involved are still uncertain. We previously reported that low Apaf1 expression partially accounts for cardiomyocyte resistance to apoptosis. Here, we extend the knowledge on the molecular basis of cardiac resistance to caspase activation by showing that the whole caspase-dependent ... More
AFLP-based transcript profiling (cDNA-AFLP) for genome-wide expression analysis.
AuthorsVuylsteke M, Peleman JD, van Eijk MJ
JournalNat Protoc
PubMed ID17545977
Although DNA microarrays are currently the standard tool for genome-wide expression analysis, their application is limited to organisms for which the complete genome sequence or large collections of known transcript sequences are available. Here, we describe a protocol for cDNA-AFLP, an AFLP-based transcript profiling method that allows genome-wide expression analysis ... More