Wright, Jonathan M.
Permanent URI for this collectionhttps://hdl.handle.net/10222/22327
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Item Open Access Jonathan M.Wright CV(2013-08-29) Wright, Jonathan M.Item Open Access Isolation and sequence of cDNA clones coding for a member of the family of high mobility group proteins (HMG-T) in trout and analysis of HMG-T-mRNA's in trout tissues(Oxford University Press, Oxford Journals, Great Clarendon Street, 1985-07) Pentecost, B. T.; Wright, Jonathan M.; Dixon, G. H.No abstract available.Item Open Access Nucleotide sequence of 5S rDNA and localization of the ribosomal RNA genes to metaphase chromosomes of the Tilapiine cichlid fish, Oreochromis niloticus(2000-10) Martins, Cesar; Wasko, Adriane P.; Oliveira, Claudio; Wright, Jonathan M.In this study, we report the cloning and nucleotide sequence of PCR-generated 5S rDNA from the Tilapiine cichlid fish, Oreochromis niloticus. Two types of 5S rDNA were detected that differed by insertions and/or deletions and base substitutions within the non-transcribed spacer (NTS). Two 5S rDNA loci were observed by fluorescent in situ hybridization (FISH) in metaphase spreads of tilapia chromosomes. FISH using an 18S rDNA probe and silver nitrate sequential staining of 5S-FISH slides showed three 18S rDNA loci that are not syntenic to the 5S rDNA loci.Item Open Access Can SINEs: A family of tRNA-derived retroposons specific to the superfamily canoidea(1994) Coltman, David W.; Wright, Jonathan M.A repetitive element of approximately 200 bp was cloned from harbour seal (Phoca vitulina concolour) genomic DNA. The sequence of the element revealed putative RNA polymerase III control boxes, a poly A tail and direct terminal repeats characteristic of SINEs. Sequence and secondary structural similarities suggest that the SINE is derived from a tRNA, possibly tRNA-alanine. Southern blot analysis indicated that the element is predominately dispersed in unique regions of the seal genome, but may also be present in other repetitive sequences, such as tandemly arrayed satellite DNA. Based on slot-blot hybridization analysis, we estimate that 1.3 x 10-6 copies of the SINE are present in the harbour seal genome; SINE copy number based on the number of clones isolated from a size-selected library, however, is an order of magnitude lower (1 - 3 x 10-5 copies), an estimate consistent with the abundance of SINEs in other mammalian genomes. Database searches found similar sequences have been isolated from dog (Canis familiaris) and mink (Musteia vison). These, and the seal SINE sequences are characterized by an internal CT dinucleotide microsatellite in the tRNA-unrelated region. Hybridization of genomic DNA from representative species of a wide range of mammalian orders to an oligonucleotide (30mer) probe complementary to a conserved region of the SINE confirmed that the element is unique to carnivores of the superfamily Canoidea.Item Open Access Nucleotide sequence, genomic organization and evolution of a major repetitive DNA family in tilapia (Oreochromis mossambicus/hornorum )(1989) Wright, Jonathan M.A highly repetitive DNA sequence from tilapia (Oreochromis mossambicus/hornorum ) has been cloned and sequenced. It is a tandemly arrayed sequence of 237 bp and constitutes 7% of the fish genome. The copy number of the repeat is approximately 3 x 10 super(5) per haploid genome. DNA sequence analysis of 7 cloned repeats revealed a high degree of conservation of the monomeric unit. Within the monomeric unit, a 9 bp AT rich motif is regularly spaced approximately 30 bp apart and may represent the progenitor of the amplified sequence. One cloned repeat, Ti-14, contained a 30 bp deletion at a position flanked by a 7 bp direct repeat. The Ti-14 sequence appears to have been amplified independently of the major 237 bp tandem array. A higher-order repeat unit, defined by longer-range periodicities revealed by restriction endonuclease digestion, is further imposed on the tandem array.Item Open Access Tidal and turbidity effects on the shallow-water fish assemblage of Kuwait Bay(1990) Abou-Seedo, F.; Clayton, DA; Wright, Jonathan M.Effects of location, diel period, tidal condition and water clarity on the size and distribution of the shallow water fish assemblage of the non-estuarine Kuwait Bay, were investigated using a beach seine and a small research trawl during spring and summer 1989. Total numbers, biomass and numbers of species differd markedly between Doha, a sandy shore environment, and Kazmah, an extensive intertidal mud flat. When fish were present in large numbers there was a marked diel effect at both locations with many more fish captured during the night. Tidal effects were influenced by turbidity and the age structure of the assemblage. In clear water during spring, very young Liza carinata from the seine catches formed shoals at the edge of the rising tide both day and night, while fish 2 mo older formed shoals only on daytime rising tides. At Kazmah during spring, high turbidity obscured any tidal effects in the seine catches. In slightly deeper water, sampled by trawl during spring, Leiognathus decorus showed an asymmetrical tidal migration.