Linked Life Data

8677258

Source:http://linkedlifedata.com/resource/pubmed/id/8677258

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1370
pubmed:dateCreated
1996-8-9
pubmed:abstractText
Primers for 18 microsatellite loci originally isolated from whiting (Merlangius merlangus, n = 6), stickleback (Gasterosteus aculeatus, n = 5) and cod (Gadus morhua, n = 7) were tested across a panel of diverse fish species, representing the three principal superclasses and most principal superorders of fish, to examine conservation of microsatellite regions across distantly related taxa. Three methods were used. First, amplified fragments were analysed by Southern blotting using the relevant microsatellite motif probes. A total of 17 of the tested primer pairs gave a product in the expected size range in at least four of 11 tested species. Second, for two study loci the amplified polymerase chain reaction products were cloned and sequenced in five fish species to reveal a high level of conservation of the flanking and microsatellite sequences. Finally, the 17 loci successfully amplified in non-source species were tested for polymorphism in groups of unrelated individuals from nine species, in several cases revealing extensive polymorphism. Levels of polymorphism were generally high in species from which the loci were derived or among closely related species. The conservation of flanking sequences for particular microsatellite motifs over the span of fish evolution represented in the test species (470 million years) far exceeds that hitherto reported and lends support to the suggestion (derived from studies of whales and marine turtles) that the rate of base substitution in nuclear and mitochondrial sequences is lower in aquatic than terrestrial organisms. A further explanation could be that these sequences, although generally considered neutral, may play an important role in eukaryotic genomes, and may be under strong selective constraints. The study suggests that heterologous primers will be a ready source of polymorphic markers among fish species, but also indicates that caution should be used in cross-species comparisons of variability.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0962-8452
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
263
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
549-57
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
470 million years of conservation of microsatellite loci among fish species.
pubmed:affiliation
University of East Anglia, School of Biological Sciences, Norwich, U.K.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't