The complex of Xenopus transcription factor IIIA (TFIIIA) with 5 S rRNA was analyzed in nuclease protection experiments using hydroxyl radical. The protection pattern reveals that TFIIIA interacts with a substantial amount of the RNA molecule, with close association between the factor and the arm of the RNA composed of helix IV-loop E-helix V. Additional sites of protection punctuate the other ...

background : nosemosis of european honey bee (apis mellifera ) is present in bee colonies world­wide. until recently, nosema apis had been regarded as the causative agent of the disease, that causes heavy economic losses in apicultures. nosema ceranae is an emerging microsporidian para­site of european honeybees, a. mellifera , but its distribution is not well known. previously, nosemosis in ho...

Insulin stimulated total RNA accretion and the incorporation of [3H]uridine into RNA in L6 skeletal-muscle myoblasts. Incorporation of uridine into the rRNA was measured after either separation of 18 S and 28 S rRNA species by agarose-gel electrophoresis or separation of dissociated 40 S and 60 S ribosomal subunits on sucrose density gradients. Both methods showed a stimulation by insulin of ur...

It has been shown' previously that the corrected sedimentation coefficients (820 W) of the ribosomes from 25 species of fungi and 25 species of bacteria, respectively, range from 76.5 to 84.5 Svedberg units (S) and from 63.8 to 72.1S, and that the difference between the arithmetic means, 81.3 and 68.4S, of these two frequency distributions is significant. Since the ribosomes from other eucaryot...

Mature Paramecium mitochondrial large subunit rRNA consists of two stable segments: a 20 S segment described previously and a unique 283-base segment similar to 5.8 S rRNAs typically found in eucaryotic cytoplasmic RNA. pBR325 clones of both gene regions from both Paramecium primaurelia and Paramecium tetraurelia were sequenced and aligned. The gene segments lie adjacent to each other very near...

1. As shown by a double-radioisotope technique in vivo, at a non-lethal dose of cycloheximide, a stimulation of nuclear RNA synthesis occurred by 12 h after the treatment; the stimulation lasted over 48 h. Analysis of radioactive nuclear RNA by gel electrophoresis demonstrated that most of the cycloheximide-stimulated synthesis could be accounted for by known rRNA precursors (45 S, 41 S, 32 S a...

micrornas constitute a group of small non-coding rnas that negatively regulate gene expression. aside from their contribution to biological and pathological pathways, altered expression of micrornas is reported in bio-fluid samples, such as serum. to employ serum's micrornas as potential biomarkers, it is crucial to develop an efficient method for microrna quantification, avoiding pre-analytica...