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W J Rutter

Publications and source records attributed to W J Rutter.

At least 199 records · Page 11Linked to original sources
PubMed1979

Isolation of yeast tRNALeu genes. DNA sequence of a cloned tRNALeu3 gene.

A library of cloned yeast DNA fragments generated by digestion of yeast DNA with the restriction endonuclease Bam HI has been screened by colony hybridization to total yeast [32P]tRNA. Four hundred colonies carrying yeast tRNA genes were isolated. By hybridization to 125I-tRNALeu3, we have isolated from this collection 14 colonies carrying fragments containing yeast tRNALeu genes. The size of the yeast Bam HI inserts ranged from 2.45 x 10(6) to 14 x 10(6) daltons. One of these fragments was mapped in detail by restriction endonuclease digestion and hybridization to 125I-tRNALeu3. The presence of a tRNALeu3 gene was confirmed by DNA sequence. The results indicate that the tRNALeu3 coding region is not co-linear with the tRNALeu3. An intervening tract of 33 base pairs interrupts the coding sequences 1 base pair past the anticodon coding region. The putative structure of a tRNALeu3 precursor is deduced in which the anticodon base pairs with residues from the intervening sequence.

Base Sequence↗
PubMed1979

Isolation of biologically active ribonucleic acid from sources enriched in ribonuclease.

Intact ribonucleic acid (RNA) has been prepared from tissues rich in ribonuclease such as the rat pancreas by efficient homogenization in a 4 M solution of the potent protein denaturant guanidinium thiocyanate plus 0.1 M 2-mercaptoethanol to break protein disulfide bonds. The RNA was isolated free of protein by ethanol precipitation or by sedimentation through cesium chloride. Rat pancreas RNA obtained by these means has been used as a source for the purification of alpha-amylase messenger ribonucleic acid.

Animals↗
PubMed1979

Nucleotide sequence of the gene coding for the major protein of hepatitis B virus surface antigen.

DNA extracted from hepatitis B virus Dane particles has been cloned in bacteria using a plasmid vector. A full-length clone has been examined by restriction endonuclease analysis, and the nucleotide sequence of an 892-base pair fragment from cloned hepatitis B viral DNA encoding the surface antigen gene is reported. The amino acid sequence deduced from the DNA indicates that the surface antigens is a protein consisting of 226 amino acids and with a molecular weight of 25,398. The portion of the gene coding for this protein apparently contains no intervening sequences.

Antigens, Surface↗
PubMed1979

Specific gene transcription in yeast nuclei and chromatin by added homologous RNA polymerases I and II.

When treated at pH less than 4.5, yeast nuclei or chromatin lose endogenous RNA synthetic activity. This activity is regained by addition of exogenous RNA polymerases. The specificity of transcription in this system by homologous RNA polymerases I and III has been investigated by gel electrophoresis, hybridization analysis, and RNase T1 mapping. Exogenous RNA polymerase I selectively transcribes rRNA genes. The transcription of these genes by polymerase I is 30- and 8-fold more selective than RNA polymerase III and Escherichia coli polymerase holoenzyme, respectively. Exogenous RNA polymerase III synthesized RNAs similar in size to authentic 5 S RNA, 4.5 S pre-tRNA, and 4 S tRNA. Eleven per cent of this RNA is 5 S RNA as determined by hybridization. Neither polymerase I nor E. coli polymerase synthesizes detectable quantities of RNA in this size range. AT1 ribonuclease digestion of 5 S RNA synthesized by exogenous RNA polymerase III acting on acid-treated chromatin gives a fragment pattern corresponding to that of 5 S RNA. Thus, RNA polymerase III transcribes the entire 5 S gene in this system.

Cell Nucleus↗
PubMed1979

Isolation and characterization of a cloned rat insulin gene.

The two nonallelic genes, insulin I and II of the rat, are separated by at least 7 kb of DNA. There is no obvious similarity in the sequence organization surrounding each gene, although the coding regions of the genes themselves share extensive homology. In three strains of rat, the insulin II gene lies predominantly on a 4.0 kb Eco RI restriction fragment, whereas the insulin I gene is located on a 9.4 kb Eco RI fragment in the Hooded strain, on a 7.2 kb Eco RI fragment in the Osborne-Mendel strain, and on both a 9.4 and a 7.2 kb Eco RI fragment in Sprague-Dawley rats. The 9.4 kb Eco RI fragment from Hooded rat DNA was isolated using the lambda cloning system, and the nucleotide sequence of this isolated rat insulin I gene and adjacent regions was determined. A translation in one frame of the sequence of the cloned gene confirms the protein sequence determined for rat pre-proinsulin I. The coding region of this gene lacks intervening sequences, although a presumptive intervening sequence of 119 bp is located in the 5 untranslated region preceding the prehormone sequence. The junctions around the 119 bp segment are identical to those which flank intervening sequences of other eucaryotic genes, AGGT. The site of polyadenylation was determined by direct sequence comparison with rat insulin cDNA clones, and a potential 5 "capping" site is proposed. A DNA sequence preceding this 5 "capping" site in the rat insulin I gene, TATAAAGC, is homologous to corresponding regions in other eucaryotic genes that have been proposed as putative promoter sites for the initiation of transcription.

Animals↗
PubMed1979

Synthesis and accumulation of proinsulin and insulin during development of the embryonic rat pancreas.

Endocrine B cells differentiate normally in embryonic rat pancreatic rudiments cultured in vitro. The specific concentration of immunoreactive insulin based on total protein increases by about 1000-fold during the developmental period, corresponding to days 13--20 of gestation. The rate of (pro)insulin synthesis, measured from the level of radioactive leucine incorporated into insulin, quantitatively accounts for the insulin accumulated during this period. In addition, the relative incorporation of leucine into proinsulin compared to insulin is constant during development and is similar to that found in the B cells of adult islets. Thus, there appears to be no significant change in the rate of conversion of proinsulin to insulin during B cell differentiation.

Animals↗
PubMed1978

Structure and processing of yeast precursor tRNAs containing intervening sequences.

We have isolated a precursor of yeast tRNATyr and shown that it contains an intervening sequence identical to that found in the gene for tRNATyr. The conformation of pre-tRNATyr is similar to that of mature tRNATyr except for the anticodon loop. The loop is sensitive to endonucleolytic cleavage by S1 nuclease near to the ends of the intervening sequence. This pre-tRNA is functionally inactive as it cannot be aminoacylated and the anticodon is not accessible for hydrogen bonding. A crude nuclear extract from yeast contains an excision-ligase activity which will process pre-tRNATyr into mature tRNATyr.

Anticodon↗
PubMed1978

Structure of yeast phenylalanine-tRNA genes: an intervening DNA segment within the region coding for the tRNA.

Sixteen bacterial clones containing sequences complementary to yeast PhetRNA were isolated from a collection of hybrid plasmids containing BamHI restriction endonuclease-generated yeast DNA fragments inserted in the plasmid vector pBR315. Ten of these clones contained hybrid plasmids with distinct BamHI fragments. The sequence of the Phe-tRNA structural genes and adjacent regions of three of these clones is reported here. In the region flanking the tRNA gene, the sequence of two of the cloned DNAs is similar; the sequence of the third varies considerably. All three of the tRNA genes are bordered by A,T-rich regions. In particular, near the region coding for the 3' end of the tRNA there is a long sequence of As in the coding strand. This is reminiscent of the region of termination of transcription of the yeast 5S rRNA gene. The sequences coding for the Phe-tRNA contain an additional segment of 18 or 19 base pairs (depending upon the clone) not predicted by the yeast Phe-tRNA sequence. These intervening segments are nearly identical in the three clones and are located within the structural gene, two base pairs from the nucleotides coding for the tRNA anticodon.

Anticodon↗
PubMed1977

Ribosomal RNA genes of Saccharomyces cerevisiae. I. Physical map of the repeating unit and location of the regions coding for 5 S, 5.8 S, 18 S, and 25 S ribosomal RNAs.

The organization of the ribosomal DNA repeating unit from Saccharomyces cerevisiae has been analyzed. A cloned ribosomal DNA repeating unit has been mapped with the restriction enzymes Xma 1, Kpn 1, HindIII, Xba 1, Bgl I + II, and EcoRI. The locations of the sequences which code for 5 S, 5.8 S, 18 S, and 25 S ribosomal RNAs have been determined by hybridization of the purified RNA species with restriction endonuclease generated fragments of the repeating unit. The position of the 5.8 S ribosomal DNA sequences within the repeat was also established by sequencing the DNA which codes for 83 nucleotides at the 5' end of 5.8 S ribosomal RNA. The polarity of the 35 S ribosomal RNA precursor has been established by a combination of hybridization analysis and DNA sequence determination and is 5'-18 S, 5.8 S, 25 S-3'.

DNA↗