Nucleic Acids Research

Wakabayashi,, T.;Kato,, H.;Tachibana,, S.

doi: 10.1093/nar/13.6.1817pmid: 4000945

Abstract The complete nucleotide sequence of mRNA for caerulein precursor in the skin of Xenopus laevis was determined. The sequence was composed of 705 bp of coding region, accounting for 234 amino acids, 58 bp of 5′-untranslated region and 158 bp of 3′-untranslated region containing two putative poly(A) signals. It coded for four caerulein peptides interspersed with three 147 bp segments (intercaerulein segment; ICS). Analyses of several caerulein encoding cDNAs revealed some interesting features of caerulein mRNA species, which were highly heterogenous and consisted of a repetition of two fundamental RNA sequences, a 45-nucleotide caerulein fragment and a 147-nucleotide ICS. The result of Northern blotting indicated that caerulein mRNA was only present in frog skin, not in stomach, upper intestine or liver. It appears that caeruelin has different physiological function(s) from mammlian gastrin and cholecystokinin-pancreozymin (CCK). The relationship of caerulein to mammalian gastrointestinal hormones is discussed. This content is only available as a PDF. © IRL Press Limited

, van den Berg, E.A;Geerse,, R.H.;Memelink,, J.;Bovenberg,, R.A.L.;Magnée,, F.A.;, van de Putte, P.

doi: 10.1093/nar/13.6.1829pmid: 2987838

Abstract A region located upstream of the uvrB promoters P1 and P2 was found to cause high plasmid loss when cloned in multicopy vectors. Two sequence elements responsible for this phenomenon were identified by mapping of spontaneous mutations that restore plasmid maintenance: a sequence known to have in vitro promoter activity and a partially overlapping sequence that shows extensive homology to recognition sites for the DnaA protein. Accordingly alterations in the level of DnaA protein in vivo were found to affect the extent of plasmid loss. A possible role for interaction of the DnaA protein with the region of interest is discussed in relation to regulation of uvrB expression. This content is only available as a PDF. Author notes 1 Present address: Laboratory of Genetics, Free University of Amsterdam, De Boelelaan 1087, 1007 MC Amsterdam, The Netherlands © IRL Press Limited

Debouck,, C.;Riccio,, A.;Schumperli,, D.;McKenney,, K.;Jeffers,, J.;Hughes,, C.;Rosenberg,, M.;Heusterspreute,, M.;Brunel,, F.;Davison,, J.

doi: 10.1093/nar/13.6.1841pmid: 3158881

Abstract We present the nucleotide sequence of the galactokinase gene ( gal K) of Escherichiacoli including its 5′ and 3′ flanking regions. This DNA sequence derives from the λga18 transducing phage and is identical to the sequence present in the gal k gene fusion vectors, pKO and pKG, commonly used to study transcriptional regulatory elements. We define the precise 3′ junction between the bacterial and phage sequences in λga18 and demonstrate that this junction prohably results from a homologous recombination event between identical 9 bp sequences common to the gal operon and phage λ. Moreover, we examine the 300 bp region located immediately beyond gal K for transcription termination function and find no gal operon terminator. Lastly, we compare the gal K genes of E . coli and the yeast S . cerevisiae and find several regions of strong homology among which is a potential ATP-binding site homology shared by a variety of ATP-binding proteins including protein kinases encoded by mammalian oncogenes. This content is only available as a PDF. Author notes 1 Present address: Istituto di Patologia Generale II, Facolta Di Medicina, Naples, Italy 2 Present address: Institut fur Molekularbiologie II, Universitat Zurich, Winterthurerstrasse 266A, CH-8057 Zurich, Switzerland 3 Present address: Laboratory of Molecular Genetics, NINCDS, NIH, Bethesda, MD 20205, USA 4 Present address: Ouachita Baptist University, Department of Chemistry, OBU Box 748, Arkadelphia, AR 71923, USA 5 Present address: University of Cambridge, Department of Pathology, Cambridge, CB2 1QP, UK © IRL Press Limited

Künzler,, Peter

doi: 10.1093/nar/13.6.1855pmid: 3889843

Abstract The slime mould Physarumpolycephalum contains 100 to 200 molecules of extrachromosomal linear DNA (PeDNA). Two sets of the 19S and 26S ribosomal genes are located on each molecule of PeDNA. In the nonmitotic phase of the cell cycle PeDNA is localised in the nucleolus. The molecules are maintained throughout vegetative growth. In order to study the signals responsible for its maintenance, PeDNA was purified and introduced into the two distantly related yeasts Saccharomycescerevisiae and Schizosaccharomycespombe Surprisingly, intact PeDNA transforms both yeasts with high frequency and PeDNA sequences are maintained In the absence of selective pressure. This content is only available as a PDF. © IRL Press Limited

Price, James, V.;Kieft, Gary, L.;Kent, Jeffrey, R.;Sievers, Eric, L.;Cech, Thomas, R.

doi: 10.1093/nar/13.6.1871pmid: 4000946

Abstract The sequence requirements for splicing of the Tetrahymena pre-rRNA have been examined by altering the rRNA gene to produce versions that contain insertions and deletions within the intervening sequence (IVS). The altered genes were transcribed and the RNA teeted for self-splicing in vitro. A number of insertions (8–54 nucleotides) at three locations had no effect on self-splicing activity. Two of these insertions, located at a site 5 nucleotides preceding the 3′-end of the IVS, did not alter the choice of the 3′ splice site. Thus the 3′ splice site is not chosen by its distance from a fixed point within the IVS. Analysis of deletions constructed at two sites revealed two structures, a hairpin loop and a stem-loop, that are entirely dispensable for IVS excision in vitro. Three other regions were found to be necessary. The regions that are important for self-splicing are not restricted to the conserved sequence element. that define this class of intervening sequences. The requirement for structures within the IVS for pre-rRNA splicing is in sharp contrast to the very limited role of IVS structure in nuclear pre-mRNA splicing. This content is only available as a PDF. Author notes + Present address: Amgen Development Inc., Boulder, CO 80301, USA § Present address: Baylor College of Medicine, Houston, TX 77030, USA * Present address: Brown University, Providence, RI 02912, USA © IRL Press Limited

Docherty,, A.J.P.;Bodmer,, M.W.;Angal,, S.;Verger,, R.;Riviere,, C.;Lowe,, P.A.;Lyons,, A.;Emtage,, J.S.;Harris,, T.J.R.

doi: 10.1093/nar/13.6.1891pmid: 3839077

Abstract Purified rat lingual lipase (EC3113), a glycoprotein of approximate molecular weight 52,000, was used to generate polyclonal antibodies which were able to recognise the denatured and deglycosylated enzyme. These immunoglobulins were used to screen a cDNA library prepared from mRNA isolated from the serous glands of rat tongue cloned in E. coli expression vectors. An almost full length cDNA clone was isolated and the nucleotide and predicted amino acid sequence obtained. Comparison with the N-terminal amino acid sequence of the purified enzyme confirmed the identity of the cDNA and indicated that there was a hydrophobic signal sequence of 18 residues. The amino acid sequence of mature rat lingual lipase consists of 377 residues and shares little hamology with porcine pancreatic lipase apart fran a short region containing a serine residue at an analogous position to the ser 152 of the porcine enzyme. This content is only available as a PDF. © IRL Press Limited

Sealey, Paul, G.;Whittaker, Paul, A.;Southern, Edwin, M.

doi: 10.1093/nar/13.6.1905pmid: 4000947

Abstract Pre-reassociation of human clone probes, containing dispersed highly repeated sequences, (e.g. Alu and KpnI families), with a large excess of sonicated total human DNA allows signal from single and low copy number components to be detected in transfer hybridisations. The signal from non-dispersed repeated sequences is reduced to single copy levels. The procedure, which is simple and quick, is illustrated using model combinations of well characterised cloned probes, and is applied to a sample of randomly chosen cosmid clones. A theoretical assessment is presented which may be useful to those wishing to use this procedure. This content is only available as a PDF. © IRL Press Limited

Buell,, Gary;Schulz,, Marie-Francoise;Selzer,, Gerald;Chollet,, Andre;Movva,, N.Rao;Semon,, Dominique;Escancz,, Sonia;Kawashima,, Eric

doi: 10.1093/nar/13.6.1923pmid: 3889844

Abstract Double-stranded DNA encoding the human hormone somatomedin-C (SMC) has been synthesized. This synthetic gene hae been inserted into a plasmid bearing the strong leftward promoter (P L ) of bacteriophage λ and expressed in E.coli . Codons for the N-terminal region of SMC which maximized the hormone's synthesis were chosen in an SMC- lac z fusion assay. The amounts of SMC accumulated in E. coli were influenced by mutations at two chromosomal loci, lon and htpR . This content is only available as a PDF. © IRL Press Limited

Margison, Geoffrey, P.;Cooper, Donald, P.;Brennand,, John

doi: 10.1093/nar/13.6.1939pmid: 3889845

Abstract Akylating agents react with various nitrogen and oxygen atoms in DNA and many of the products are substrates repair processes. Oxygen atom derivatives such as 0 6 -methylguanine ( 0 6 -meG) 0 4 -methylthymine and methylphosphotriesters (MP) have been shown to undergo repair by methyl group removal. The proteins involved in the latter reaction can be considered to be methyltranferases (MT) because their action results in the transfer of the methyl group to a cysteine residue within a polypeptide. A rapid and sensitive assay for MT activity has been developed and used to screen extracts of bacteria harbouring an E.coli genomic DNA library carried in a glasmid vector. We report here the cloning of an E.coli gene coding for 0 6 -meG and MP MT repair functions. These two activities reside on a 37Kd protein that can undergo a host-dependent cleavage to produce an l8Kd protein which contains only 0 6 -meG MT and a l3Kd protein which contains only MP MT. This content is only available as a PDF. Author notes 3 Present address: Cancer Research Unit, University of York, York YO 5DU. UK © IRL Press Limited

Buchberg, Arthur, M.;Kinniburgh, Alan, J.

doi: 10.1093/nar/13.6.1953pmid: 4000948

Abstract We have isolated cDNA clones for mRNAS that are Induced by porphyria from a mouse liver library. Of the three inducible clones isolated, we have identified one as being apolipoprotein A-IV (apo A-IV) by its extensive homology with a rat apollpoprotein A-IV cDNA sequence. The level of liver apo A-IV mRNA increases rapidly in response to either of two porphyrogenic drugs. When the ferrochelatase-inhibited drug, 3,5-dicarbethoxy- 1,4,-dihydrocoilidine (DDC) is used, a 6 and 28 fold induction of liver apo A-IV mRNA is observed in male and female mice, respectively, if the heme-destroying porphyrogenic drug, allylisopropylacetamide (AIA) is the inducing agent, liver apo A-IV mRNA levels increase 2–3 fold in both males and females. The level of apo A-IV mRNA reaches a maximum within 6–10 hr. after drug administration. Intestine apo A-IV mRNA levels do not change during either of these drug-induced porphyrias. RNA from acute-phase responsive liver or liver from mice treated with bilirubin, porphobilinogen, or protoporphyrin IX show no increase in apo A-lV mRNA. These results indicate that apo A-IV induction is tied to a disruption in porphyrin-heme biosynthesis but is not directly affected by several heme intermediates nor by the major heme degradation product, bilirubin. This content is only available as a PDF. © IRL Press Limited