Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1990-3-14
pubmed:abstractText
Restriction site variation in DNA that encodes rRNA (rDNA) was surveyed among 714 offspring within 31 lineages (26 genotypes) of obligate asexually reproducing Taraxacum officinale (dandelions). Although clonal offspring are expected, plants with nonparental rDNA were produced from two parents that were themselves siblings (same genotype). The variation is best characterized by the loss of an EcoRI restriction site that maps to the spacer region in the parental rDNA and is most likely involved in amplification of rare or unique rDNA repeats. In one family, 41 surveyed offspring lacked the EcoRI site. In the other family, only 1 of 26 offspring lost the EcoRI site. Other classes of DNA surveyed, chloroplast DNA and the alcohol dehydrogenase 2 gene (Adh2), showed no variation. However, offspring with nonparental rDNA also had nonparental alcohol dehydrogenase 1 (Adh1) restriction fragments. Because somatic mutations in plants can be incorporated into reproductive tissue, we propose that somatic events affecting at least both multicopy rDNA and DNA homologous to the maize Adh1 gene occurred at different developmental times in the two families. An event early in development would result in all variant offspring; an event late in development would result in a single variant offspring. These results support the view that mutation (in the broad sense) influences the level of genotypic variation in asexual organisms, which may facilitate adaptive evolution of asexual species.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-17246333, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-17246339, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-2851705, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-2870521, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-2987807, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-3029671, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-3328815, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-4059056, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-4208547, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-6096873, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-6312838, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-6328449, http://linkedlifedata.com/resource/pubmed/commentcorrection/2300590-6987539
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0027-8424
pubmed:author
pubmed:issnType
Print
pubmed:volume
87
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
998-1002
pubmed:dateRevised
2010-9-9
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Genotypic variation within asexual lineages of Taraxacum officinale.
pubmed:affiliation
Department of Biology, Washington University, Saint Louis, MO 63130.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.