In small oocytes of Xenopus species, two sets of 5S RNA genes, oocyte-type and somatic-type, are fully activated. The 5S RNA transcripts are temporarily stored, half in association with TFIIIA to form a 7S particle, the other half in association with tRNA and two proteins (p48 and p43) to form a 42S particle. It has been established previously that TFIIIA binds to the internal control region of...

Footprint competition assays are utilized to study the binding of Xenopus transcription factor A to a variety of single-stranded nucleic acids. The addition of Xenopus oocyte, yeast, or wheat germ 5S RNA as footprint competitors reveals that factor A binds these 5S RNAs with similar affinity. In contrast, factor A does not bind to E.coli 5S RNA or wheat germ tRNA in this assay. Factor A binding...

In eukaryotes, three of the four ribosomal RNAs (rRNAs)—the 5.8S, 18S, and 25S/28S rRNAs—are processed from a single pre-rRNA transcript and assembled into ribosomes. The fourth rRNA, the 5S rRNA, is transcribed by RNA polymerase III and is assembled into the 5S ribonucleoprotein particle (RNP), containing ribosomal proteins Rpl5/uL18 and Rpl11/uL5, prior to its incorporation into preribosomes....

Three stereoisomeric inhibitors of Pin1: (2R,5S)-, (2S,5R)- and (2S,5S)-Ac-pSer-Ψ[(Z)CH = C]-pipecolyl(Pip)-2-(2-naphthyl)ethylamine 1, that mimic L-pSer-D-Pro, D-pSer-L-Pro, and D-pSer-D-Pro amides respectively, were synthesized by a 13-step route. The newly formed stereogenic centers in the pipecolyl ring were introduced by Luche reduction, followed by stereospecific [2,3]-Still-Wittig rearra...

To address understanding the organization of the 5S rRNA multigene family in the fish genome, the nucleotide sequence and organization array of 5S rDNA were investigated in the genus Leporinus, a representative freshwater fish group of South American fauna. PCR, subgenomic library screening, genomic blotting, fluorescence in situ hybridization, and DNA sequencing were employed in this study. Tw...

Individual bulge loops present in Xenopus 5S RNA (positions 49A-A50 in helix III, C63 in helix II and A83 in helix IV), were deleted by site directed mutagenesis. The interaction of these mutant 5S RNA molecules with TFIIIA was measured by a direct binding assay and a competition assay. The results of these experiments show that none of the bulged nucleotides in Xenopus 5S RNA are required for ...

The hypotheses that normal children accumulate less reactive inhibition than brain-damaged and behavior-disordered 5s and that brain damage produces extraverted behavior were substantially supported by the results of 4 psychomotor and perceptual tests. 75 children (25 brain damaged, 25 behavior disordered, and 25 normals) of at least average intelligence (age range 11-15) were sampled. The resu...

The plant-specific RNA polymerases Pol IV and Pol V are essential to RNA-directed DNA methylation (RdDM), which also requires activities from RDR2 (RNA-Dependent RNA Polymerase 2), DCL3 (Dicer-Like 3), AGO4 (Argonaute), and DRM2 (Domains Rearranged Methyltransferase 2). RdDM is dedicated to the methylation of target sequences which include transposable elements, regulatory regions of several pr...

As part of a continuing study on the origin of genetic coding and the process of protein synthesis, we have compared sequences of a large number of transfer RNAs and several 5S ribosomal RNAs using automated routines. Transfer RNAs were found to exhibit a high degree of matching with 5S rRNAs. These matches are considered to be indicative of sequence homology, reflecting common ancestry of the ...

Leukotriene B (LTB), a potent lipid chemotactic factor for neutrophils, is 5S,12R-dihydroxy-6,14-cis,8,10-trans-eicosatetraenoic acid (Fig 1), based upon direct comparison of natural LTB with synthetic 5S,12R-dihydroxy-6,8,10,14-eicosatetraenoic acid (5,12-di-HETE) stereoisomers in three biological assays. Of the six synthetic stereoisomers evaluated, only the 5S,12R,6,14-cis,8,10-trans compoun...