Linked Life Data

2071024

Source:http://linkedlifedata.com/resource/pubmed/id/2071024

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1991-8-22
pubmed:abstractText
Recent genetic analyses have demonstrated that self-incompatibility in flowering plants derives from the coordinated expression of a system of loci. To address the selective mechanisms through which a genetic system of this kind evolves, I present a three-locus model for the origin of gametophytic self-incompatibility. Conventional models assume that a single locus encodes all physiological effects associated with self-incompatibility and that the viability of offspring depends only on whether they were derived by selfing or outcrossing. My model explicitly represents the genetic determination of offspring viability by a locus subject to symmetrically overdominant selection. Initially, the level of expression of the proto-S locus is insufficient to induce self-incompatibility. Weak gametophytic self-incompatibility arises upon the introduction of a rare allele at an unlinked modifier locus which enhances the expression of the proto-S locus. While conventional models predict that the origin of self-incompatibility requires at least two- to threefold levels of inbreeding depression, I find that the comparatively low levels of inbreeding depression generated by a single overdominant locus can ensure the invasion of an enhancer of self-incompatibility under sufficiently high rates of receipt of self-pollen. Associations among components of the incompatibility system promote the origin of self-incompatibility. Enhancement of heterozygosity at the initially neutral proto-S locus improves offspring viability through associative overdominance. Further, the modifier that enhances the expression of self-incompatibility develops a direct association with heterozygosity at the overdominant viability locus. These results suggest that the evolutionary processes by which incompatibility systems originate may differ significantly from those associated with their breakdown. The genetic mechanism explored here may apply to the evolution of other systems that restrict reproduction, including maternal-fetal incompatibility in mammals.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-1196352, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-16593944, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-16593966, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-16666539, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-17245959, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-17246494, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-2237440, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-2535547, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-2594090, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-2917711, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-2917712, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-3058160, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-3232118, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-3787502, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-4206458, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-5728745, http://linkedlifedata.com/resource/pubmed/commentcorrection/2071024-7141223
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0016-6731
pubmed:author
pubmed:issnType
Print
pubmed:volume
128
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
453-69
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
On the evolution of genetic incompatibility systems. VI. A three-locus modifier model for the origin of gametophytic self-incompatibility.
pubmed:affiliation
Department of Zoology, Duke University, Durham, North Carolina 27706.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Review