Heterogeneity of transposon expression and activation of the repressive network in human fetal germ cells.

Epigenetic resetting in germ cells during development de-represses transposable elements (TEs). piRNAs protect fetal germ cells by targeted mRNA destruction and deposition of repressive epigenetic marks. Here, we provide the first evidence for an active piRNA pathway and TE repression in germ cells of human fetal testis.

Lingunite-a high-pressure plagioclase polymorph at mineral interfaces in doleritic rock of the Lockne impact structure (Sweden).

Lingunite nanocrystals and amorphous plagioclase (maskelynite) are identified at the contacts between augite and labradorite wedge-shaped interfaces in the doleritic rocks of the Lockne impact structure in Sweden. The occurrence of lingunite suggests that the local pressure was above 19 GPa and the local temperature overwhelmed 1000 °C. These values are up to 10 times higher than previous values estimated numerically for bulk pressure and temperature.

hnRNP F complexes with tristetraprolin and stimulates ARE-mRNA decay.

The tristetraprolin (TTP) family of zinc-finger proteins, TTP, BRF1 and BRF2, regulate the stability of a subset of mRNAs containing 3'UTR AU-rich elements (AREs), including mRNAs coding for cytokines, transcription factors, and proto-oncogenes. To better understand the mechanism by which TTP-family proteins control mRNA stability in mammalian cells, we aimed to identify TTP- and BRF1-interacting proteins as potential TTP-family co-factors. This revealed hnRNP F as a prominent interactor of TTP and BRF1.

Regulated and quality-control mRNA turnover pathways in eukaryotes.

Gene expression can be regulated at multiple levels, including transcription, RNA processing, RNA localization, translation and, finally, RNA turnover. RNA degradation may occur at points along the processing pathway or during translation as it undergoes quality control by RNA surveillance systems. Alternatively, mRNAs may be subject to regulated degradation, often mediated by cis-encoded determinants in the mRNA sequence that, through the recruitment of trans factors, determine the fate of the mRNA.

Selective apoptosis of breast cancer cells by siRNA targeting of BORIS.

Brother of the regulator of imprinted sites (BORIS) is an epigenetically acting transcription factor which represses the tumor inhibitor functions of the tumor suppressor protein CTCF. BORIS expression has not been documented in adult females, making it an exciting molecular target for drug development in breast cancer. Previously, we demonstrated that vaccination of mice with zing-finger (ZF)-deleted non-functional BORIS results in regression of breast cancer and generation of potent anti-tumor immune responses.

The Cech Symposium: a celebration of 25 years of ribozymes, 10 years of TERT, and 60 years of Tom.

The Cech Symposium was held in Boulder, Colorado, on July 12-13, 2007, to celebrate a triple anniversary: 25 years since the first publication reporting RNA self-splicing, 10 years since the identification of reverse transcriptase motifs in the catalytic subunit of telomerase, and 60 years since the birth of Thomas R. Cech. Past and present members of the Cech laboratory presented on their current research, which branched into many categories of study including RNA-mediated catalysis, telomerase and telomeres, new frontiers in nucleic acids, alternative splicing, as well as scientific research with direct medical applications.

Molecular cloning of the baboon UDP-glucuronosyltransferase 1A gene family: evolution of the primate UGT1 locus and relevance for models of human drug metabolism.

Background: Glucuronidation by the UDP glucuronosyltransferase 1A enzymes (UGT1As) is a major pathway for elimination of drugs and endogenous substances, such as bilirubin.

Objective: To identify the baboon UGT1A gene family, compare it with that of the human, and evaluate the baboon as a model for human glucuronidation.

Methods And Results: Aligning the human and baboon UGT1 loci identified rearrangements occurring since the divergence of baboons and humans.

Induction of antitumor immunity through xenoplacental immunization.

Historically cancer vaccines have yielded suboptimal clinical results. We have developed a novel strategy for eliciting antitumor immunity based upon homology between neoplastic tissue and the developing placenta. Placenta formation shares several key processes with neoplasia, namely: angiogenesis, activation of matrix metalloproteases, and active suppression of immune function.

Fetal morphine metabolism and clearance are constant during late gestation.

Fetal metabolism significantly contributes to the clearance of drugs from the fetus. To understand how the changes in fetal metabolism expected in late gestation alter fetal drug clearance, serial measurements of morphine metabolism were made in the fetal baboon over the latter third of gestation. Clearance and metabolism were evaluated in the context of fetal growth, onset of labor, and the administration of classical enzyme induction agents.

Microstructure analysis of a carbon-carbon composite using argon ion etching.

The microstructure of carbon-carbon composites obtained by chemical vapor infiltration of a carbon fiber felt was comparatively studied by reflection light microscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), and laser scanning confocal microscopy (LSCM). Ar+ ion etching was used to reveal and distinguish structural units of the pyrolytic carbon matrix. Mechanically polished samples, polished and subsequently ion etched samples, and fractured samples were compared.

Microtubule and Rac 1-dependent F-actin in growth cones.

Extracellular cues control the rate and direction of growth of neuronal processes in large part by regulating the cytoskeleton of the growth cone. The actin filament network of the peripheral region is thought to be the primary target for these cues, with consequences for the advance and organization of microtubules. Binding of laminin to integrin receptors is a cue that accelerates the growth of processes from many types of neurons.