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T P Birt

Publications and source records attributed to T P Birt.

7 recordsLinked to original sources
PubMed1997

Intron variation in marbled murrelets detected using analyses of single-stranded conformational polymorphisms.

Combination of the targeted amplification of nuclear introns and the analysis of single-stranded conformational polymorphisms has the potential to provide an inexpensive, rapid, versatile and sensitive genetic assay for evolutionary studies and conservation. We are developing primers and protocols to analyse nuclear introns in vertebrates, and are testing them in a population genetic study of marbled murrelets Brachyramphus marmoratus. Here we present protocols and results for introns for aldolase B, alpha-enolase, glyceraldehyde-3-phosphate dehydrogenase and lamin A. Results suggest that this approach presents a potentially powerful method for detecting genetic variation within and among local populations and species of animals: (i) a variety of genes can be surveyed, including genes of special interest such as those involved in disease resistance; (ii) assays are rapid and relatively inexpensive; (iii) large numbers of genes can be assayed, enabling accurate estimation of variation in the total genome; (iv) almost any mutation can be detected in the genes amplified; (v) the exact nature of variation can be investigated by sequence analysis if desired; (vi) statistical methods previously developed for proteins and/or sequence data can be used; (vii) protocols can be easily transferred to other species and other laboratories; and (viii) assays can be performed on old or degraded samples, blood or museum skins, so that animals need not be killed. Results of analyses for murrelets support earlier evidence that North American and Asiatic subspecies represent reproductively isolated species, and that genetic differences exist among murrelets from different sites within North America.

Amino Acid Sequence↗
PubMed1992

Cytochrome-b sequence variation among parrots.

The nucleotide sequence of a 307 bp fragment of the mitochondrial cytochrome-b gene was determined for 12 species of parrot, using the polymerase chain reaction and direct sequencing. Sequence divergence ranged from 26-54 differences in pairwise comparisons, with the majority of base substitutions occurring at third positions of codons. The transition:transversion ratio was determined to be higher (approximately 24.3:1) in recently divergent parrot lineages than has generally been observed in other groups. Strongly biased base composition, particularly at the third position of codons, is evident among the sequences. Phylogenetic relationships among more divergent taxa were estimated, using only transversion substitutions, while all the substitutions were useful for closely related taxa. The African genera Psittacus and Poicephalus are closely related, in contrast to the Australian genera Nymphicus, Purpureicephalus and Melopsittacus, which represent more divergent lineages. The cockatoos appear to represent an ancient lineage within the parrots.

Animals↗
PubMed1989

Organisation of the mitochondrial genome from Atlantic salmon (Salmo salar).

A restriction map of Atlantic salmon mitochondrial DNA was constructed. The smallest XbaI fragment of the salmon mitochondrial genome was cloned and subjected to partial DNA sequence analysis. This fragment contains the genes for ATPase 6 and cytochrome oxidase III. The putative organisation of the mitochondrial genome relative to the physical map is shown.

Amino Acid Sequence↗
PubMed1988

Palmitate-binding, serum albumin-like proteins in salmonids.

There has been considerable controversy over the existence of serum albumin in fish. One of the physiological functions of albumin is to bind free fatty acids. This characteristic was used to screen the plasma of seven species of salmonids. Each species contains a protein fraction that (i) binds palmitate, (ii) has a molecular mass similar to that of human serum albumin, and (iii) is one of the most rapidly migrating proteins when salmonid plasma is subjected to anodal polyacrylamide gel electrophoresis. We conclude therefore, that salmonids have serum albumins that are homologous to the serum albumin of higher vertebrates.

Animals↗
PubMed1988

Cloning and sequence analysis of an XbaI fragment of rainbow trout mitochondrial DNA.

A 2.4 kbp XbaI fragment of rainbow trout mitochondrial DNA was cloned into pTZ18R. DNA sequence analysis reveals that this segment of the genome encodes URF3, tRNA(Arg), URF4L and URF4 in the same orientation as other vertebrate mitochondrial genomes. Comparison of these segments of the rainbow trout mitochondrial genome with the corresponding sequences in human mitochondrial DNA shows that approximately 60% of the nucleotides are the same in both species.

Amino Acid Sequence↗