Genetic interaction between two unlinked loci underlies the loss of self-incompatibility in Arabidopsis lyrata

AbstractAs the first step towards the evolution of selfing from obligate outcrossing, identifying the key mutations underlying the loss of self-incompatibility is of particular interest. However, our current knowledge is primarily based on sequence-based comparisons between selfing species and their self-incompatible relatives, which makes it hard to distinguish causal from secondary mutations. To by-pass this problem, we inferred the genetic basis of the loss of self-incompatibility by intercrossing plants from twelve geographically interspersed outcrossing and selfing populations of North-American Arabidopsis lyrata and determining the breeding system of 1,580 progeny. Self-incompatibility was not restored after crosses between different self-compatible populations. Equal frequencies of self-compatible and self-incompatible progeny emerged from crosses between parents with different breeding systems. We propose a two-locus genetic model for the loss of self-incompatibility in which specific S-locus haplotypes (S1 and S19) are associated with loss of self-incompatibility through their interaction with an unlinked modifier.

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RECONSTRUCTING ORIGINS OF LOSS OF SELF-INCOMPATIBILITY AND SELFING IN NORTH AMERICAN ARABIDOPSIS LYRATA: A POPULATION GENETIC CONTEXT

Evolution ◽

10.1111/j.1558-5646.2010.01094.x ◽

2010 ◽

Vol 64 (12) ◽

pp. 3495-3510 ◽

Cited By ~ 64

Author(s):

John Paul Foxe ◽

Marc Stift ◽

Andrew Tedder ◽

Annabelle Haudry ◽

Stephen I. Wright ◽

...

Keyword(s):

North American ◽

Population Genetic ◽

Self Incompatibility ◽

Arabidopsis Lyrata ◽

Loss Of Self ◽

Genetic Context

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Faculty Opinions recommendation of Recent speciation of Capsella rubella from Capsella grandiflora, associated with loss of self-incompatibility and an extreme bottleneck.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1158981.620807 ◽

2009 ◽

Author(s):

Michael Lenhard ◽

Adrien Sicard

Keyword(s):

Self Incompatibility ◽

Loss Of Self ◽

Capsella Rubella

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Do s genes or deleterious recessives control late-acting self-incompatibility in Handroanthus heptaphyllus (Bignoniaceae)? A diallel study with four full sib progeny arrays

Annals of Botany ◽

10.1093/aob/mcab031 ◽

2021 ◽

Author(s):

Marta B Bianchi ◽

Thomas R Meagher ◽

Peter E Gibbs

Keyword(s):

Genetic Control ◽

Inbreeding Depression ◽

Fruit Set ◽

Genetic Model ◽

Pollen Tubes ◽

Self Incompatibility ◽

Significant Difference ◽

Partial Embryo ◽

Ovule Penetration ◽

S Genes

Abstract Background and Aims Genetically controlled self-incompatibility (SI) mechanisms constrain selfing and thus have contributed to the evolutionary diversity of flowering plants. In homomorphic gametophytic SI (GSI) and homomorphic sporophytic SI (SSI), genetic control is usually by a single multi-allelic locus S. Both GSI and SSI prevent self pollen tubes reaching the ovary and so are pre-zygotic in action. In contrast, in taxa with late-acting self-incompatibility (LSI), rejection is often post-zygotic, since self-pollen tubes grow to the ovary where fertilization may occur prior to floral abscission. Alternatively, lack of self fruit set could be due to early-acting inbreeding depression (EID). The aim of our study was to investigate mechanisms underlying lack of selfed fruit set in Handroanthus heptaphyllus in order to assess the likelihood of LSI versus EID. Methods We employed four full sib diallels to study the genetic control of LSI in Handroanthus heptaphyllus using a precociously flowering variant. We also used fluorescence microscopy to study the incidence of ovule penetration by pollen tubes in pistils that abscised following pollination or initiated fruits. Key Results All diallels showed reciprocally cross-incompatible full-sibs (RCI), reciprocally cross compatible full-sibs (RCC), and non-reciprocally compatible full-sibs (NRC) in almost equal proportions. There was no significant difference between the incidence of ovule penetrations in abscised pistils following self- and cross-incompatible pollinations, but those in successful cross pollinations were around twofold greater. Conclusions A genetic model postulating a single S locus with four s alleles, one of which, in the maternal parent, is dominant to the other three, will produce RCI, RCC and NRC situations each at 33 %, consistent with our diallel results. We favour this simple genetic control over an early-acting inbreeding depression (EID) explanation since none of our pollinations, successful or unsuccessful, resulted in partial embryo development, as would be expected under a whole genome EID effect.

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Homology-Based Interactions between Small RNAs and Their Targets Control Dominance Hierarchy of Male Determinant Alleles of Self-Incompatibility in Arabidopsis lyrata

International Journal of Molecular Sciences ◽

10.3390/ijms22136990 ◽

2021 ◽

Vol 22 (13) ◽

pp. 6990

Author(s):

Shinsuke Yasuda ◽

Risa Kobayashi ◽

Toshiro Ito ◽

Yuko Wada ◽

Seiji Takayama

Keyword(s):

Dominance Hierarchy ◽

Male Dominance ◽

Self Incompatibility ◽

Arabidopsis Halleri ◽

Plant Family ◽

Arabidopsis Lyrata ◽

Multiple Networks ◽

Target Sites ◽

Gains And Losses ◽

Linear Dominance Hierarchy

Self-incompatibility (SI) is conserved among members of the Brassicaceae plant family. This trait is controlled epigenetically by the dominance hierarchy of the male determinant alleles. We previously demonstrated that a single small RNA (sRNA) gene is sufficient to control the linear dominance hierarchy in Brassica rapa and proposed a model in which a homology-based interaction between sRNAs and target sites controls the complicated dominance hierarchy of male SI determinants. In Arabidopsis halleri, male dominance hierarchy is reported to have arisen from multiple networks of sRNA target gains and losses. Despite these findings, it remains unknown whether the molecular mechanism underlying the dominance hierarchy is conserved among Brassicaceae. Here, we identified sRNAs and their target sites that can explain the linear dominance hierarchy of Arabidopsis lyrata, a species closely related to A. halleri. We tested the model that we established in Brassica to explain the linear dominance hierarchy in A. lyrata. Our results suggest that the dominance hierarchy of A. lyrata is also controlled by a homology-based interaction between sRNAs and their targets.

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Interaction Between Ploidy, Breeding System, and Lineage Diversification

10.1101/709329 ◽

2019 ◽

Cited By ~ 1

Author(s):

Rosana Zenil-Ferguson ◽

J. Gordon Burleigh ◽

William A. Freyman ◽

Boris Igić ◽

Itay Mayrose ◽

...

Keyword(s):

Breeding System ◽

Whole Genome Duplication ◽

Genome Duplication ◽

Whole Genome ◽

Self Incompatibility ◽

Evolutionary Pathway ◽

Diversification Rates ◽

Extinction Rates ◽

Biological Hierarchy ◽

Lineage Diversification

AbstractIf particular traits consistently affect rates of speciation and extinction, broad macroevolutionary patterns can be understood as consequences of selection at high levels of the biological hierarchy. Identifying traits associated with diversification rate differences is complicated by the wide variety of characters under consideration and the statistical challenges of testing for associations from comparative phylogenetic data. Ploidy (diploid vs. polyploid states) and breeding system (self-incompatible vs. self-compatible states) have been repeatedly suggested as possible drivers of differential diversification. We investigate the connections of these traits, including their interaction, to speciation and extinction rates in Solanaceae. We show that the effect of ploidy on diversification can be largely explained by its correlation with breeding system and that additional unknown factors, alongside breeding system, influence diversification rates. These results are largely robust to allowing for diploidization. Finally, we find that the most common evolutionary pathway to polyploidy in Solanaceae occurs via direct breakdown of self-incompatibility by whole genome duplication, rather than indirectly via breakdown followed by polyploidization.

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Interval mapping of viability loci causing heterosis in Arabidopsis.

Genetics ◽

10.1093/genetics/140.3.1105 ◽

1995 ◽

Vol 140 (3) ◽

pp. 1105-1109

Author(s):

T Mitchell-Olds

Keyword(s):

Genetic Basis ◽

Chromosomal Region ◽

Empirical Studies ◽

Genetic Diseases ◽

Short Interval ◽

Interval Mapping ◽

Hybrid Vigor ◽

Breeding Systems ◽

Mapping Procedure ◽

Chromosome I

Abstract The genetic basis of heterosis has implications for many problems in genetics and evolution. Heterosis and inbreeding depression affect human genetic diseases, maintenance of genetic variation, evolution of breeding systems, agricultural productivity, and conservation biology. Despite decades of theoretical and empirical studies, the genetic basis of heterosis has remained unclear. I mapped viability loci contributing to heterosis in Arabidopsis. An overdominant factor with large effects on viability mapped to a short interval on chromosome I. Homozygotes had 50% lower viability than heterozygotes in this chromosomal region. Statistical analysis of viability data in this cross indicates that observed viability heterosis is better explained by functional overdominance than by pseudo-overdominance. Overdominance sometimes may be an important cause of hybrid vigor, especially in habitually inbreeding species. Finally, I developed a maximum likelihood interval mapping procedure that can be used to examine chromosomal regions showing segregation distortion or viability selection.

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Etiopathogenetic aspects of central (hypogonadotropic) hypogonadism in female

Medical Herald of the South of Russia ◽

10.21886/2219-8075-2019-10-4-15-27 ◽

2019 ◽

Vol 10 (4) ◽

pp. 15-27

Author(s):

A. S. Loktionova ◽

I. A. Ilovayskaya

Keyword(s):

Genetic Basis ◽

Functional Form ◽

Current Knowledge ◽

Hypogonadotropic Hypogonadism ◽

Biological Action ◽

Social Concern ◽

Human Female ◽

Intact State ◽

Structural Disorders ◽

Infertile Couples

Central hypogonadism (CH) is a rare endocrine disorder caused by the disfunction of production, secretion and/or biological action of gonadotropin-releasing hormone (GnRH), which is the main hormonal regulator of hypothalamo-pituitarygonadal axis in human. Female CH is important medical and social concern due to large amount of infertile couples. Etiological structure of this condition is heterogeneous and diff ers between congenital and acquired forms. Congenital forms have a genetic predisposition: currently about 50 genes associated with CH have been found. However, genetic basis can be identifi ed just in half of CH cases. Speaking about acquired forms of CH, important to pay attention on hypothalamo-pituitary area condition. In case of intact state the functional form of CH can be diagnosed, the presence of structural disorders in this area speaks in favor of the organic cause of CH. In this review are summarized current knowledge in the fi eld of etiology and pathogenesis of female central hypogonadism.

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