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June B. Nasrallah - One of the best experts on this subject based on the ideXlab platform.
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plant mating systems Self Incompatibility and evolutionary transitions to Self fertility in the mustard family
Current Opinion in Genetics & Development, 2017Co-Authors: June B. NasrallahAbstract:Flowering plants have evolved diverse mechanisms that promote outcrossing. The most widespread of these outbreeding devices are Self-Incompatibility systems, the highly selective prefertilization mating barriers that prevent Self-fertilization by disrupting pollen–pistil interactions. Despite the advantages of outcrossing, loss of Self-Incompatibility has occurred repeatedly in many plant families. In the mustard family, the highly polymorphic receptors and ligands that mediate the recognition and inhibition of Self-pollen in Self-Incompatibility have been characterized and the 3D structure of the receptor–ligand complex has been solved. Sequence analyses and empirical studies in Self-incompatible and Self-compatible species are elucidating the genetic basis of switches from the outcrossing to Selfing modes of mating and beginning to provide clues to the diversification of the Self recognition repertoire.
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Self Incompatibility in brassicaceae crops lessons for interspecific Incompatibility
Breeding Science, 2014Co-Authors: Hiroyasu Kitashiba, June B. NasrallahAbstract:Most wild plants and some crops of the Brassicaceae express Self-Incompatibility, which is a mechanism that allows stigmas to recognize and discriminate against “Self” pollen, thus preventing Self-fertilization and inbreeding. Self-Incompatibility in this family is controlled by a single S locus containing two multiallelic genes that encode the stigma-expressed S-locus receptor kinase and its pollen coat-localized ligand, the S-locus cysteine-rich protein. Physical interaction between receptor and ligand encoded in the same S locus activates the receptor and triggers a signaling cascade that results in inhibition of “Self” pollen. Sequence information for many S-locus haplotypes in Brassica species has spurred studies of dominance relationships between S haplotypes and of S-locus structure, as well as the development of methods for S genotyping. Furthermore, molecular genetic studies have begun to identify genes that encode putative components of the Self-Incompatibility signaling pathway. In parallel, standard genetic analysis and QTL analysis of the poorly understood interspecific Incompatibility phenomenon have been initiated to identify genes responsible for the inhibition of pollen from other species by the stigma. Herewith, we review recent studies of Self-Incompatibility and interspecific Incompatibility, and we propose a model in which a universal pollen-inhibition pathway is shared by these two Incompatibility systems.
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Self-Incompatibility in the Brassicaceae
The Plant Cell, 2010Co-Authors: June B. NasrallahAbstract:Flowering plants have evolved several mechanisms for controlling pollination. Genetic Self-Incompatibility is one of the most elaborate and “smart” systems known to date. In the Brassicaceae, recognition of “Self” pollen in the Self-Incompatibility response is based on highly specific interactions between matched stigma surface receptors and pollen coat ligands encoded by haplotypes of the S locus, which triggers arrest of pollen tube development. This chapter presents a brief historical account of the analysis of SI in the Brassicaceae, an overview of our current understanding of the recognition and response phases of SI, and a summary of progress made in elucidating the genetic basis of loss of SI and switches to Self-fertility in various lineages, with an emphasis on knowledge gained from analysis of a recently developed transgenic Arabidopsis thaliana Self-incompatible model.
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complex networks of Self Incompatibility signaling in the brassicaceae
Current Opinion in Plant Biology, 2010Co-Authors: Titima Tantikanjana, Mikhail E Nasrallah, June B. NasrallahAbstract:The Self-pollination barrier of Self-Incompatibility in the Brassicaceae is based on the activity of a polymorphic stigma receptor and its pollen ligand, whose allele–specific interaction triggers a signaling cascade within the stigma epidermal cell that culminates in the inhibition of pollen tube development. Recent analyses have identified signaling intermediates and revealed unexpected cross-talk between Self-Incompatibility signaling and pistil development. The Self-Incompatibility response is now thought to be based on a phosphorylation and ubiquitin-mediated degradation pathway that inhibits the secretion of factors required for successful pollination. Because manipulation of the identified signaling intermediates results in only partial disruption of the Self-Incompatibility reaction, this pathway likely functions in conjunction with other as-yet unidentified signaling pathways to effect complete inhibition of Self-pollen.
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Molecular biology of Self- Incompatibility in plants
Trends in Genetics, 2002Co-Authors: Mikhail E Nasrallah, June B. NasrallahAbstract:Abstract Self-Incompatibility responses, genetically determined by alleles at the S locus, prevent Self-fertilization in many species of flowering plants. Recent biochemical and genetic studies on families with sporophytic or gametophytic control of Incompatibility suggest that S alleles encode specific glycoproteins expressed in the pistil and pollen. Self-Incompatibility sequences are conserved within families. In Brassica (sporophytic control) different S alleles show strong homology, and may differ by a number of small replacements and rearrangements.
Daphne R. Goring - One of the best experts on this subject based on the ideXlab platform.
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Generation of Transgenic Self-Incompatible Arabidopsis thaliana Shows a Genus-Specific Preference for Self-Incompatibility Genes.
Plants (Basel Switzerland), 2019Co-Authors: Tong Zhang, Daphne R. Goring, Guilong Zhou, Xiaomei Liang, Stuart Macgregor, Bin Yi, Jinxiong Shen, Jinxing TuAbstract:Brassicaceae species employ both Self-compatibility and Self-Incompatibility systems to regulate post-pollination events. Arabidopsis halleri is strictly Self-incompatible, while the closely related Arabidopsis thaliana has transitioned to Self-compatibility with the loss of functional S-locus genes during evolution. The downstream signaling protein, ARC1, is also required for the Self-Incompatibility response in some Arabidopsis and Brassica species, and its gene is deleted in the A. thaliana genome. In this study, we attempted to reconstitute the SCR-SRK-ARC1 signaling pathway to restore Self-Incompatibility in A. thaliana using genes from A. halleri and B. napus, respectively. Several of the transgenic A. thaliana lines expressing the A. halleri SCR13-SRK13-ARC1 transgenes displayed Self-Incompatibility, while all the transgenic A. thaliana lines expressing the B. napus SCR1-SRK1-ARC1 transgenes failed to show any Self-pollen rejection. Furthermore, our results showed that the intensity of the Self-Incompatibility response in transgenic A. thaliana plants was not associated with the expression levels of the transgenes. Thus, this suggests that there are differences between the Arabidopsis and Brassica Self-Incompatibility signaling pathways, which perhaps points to the existence of other factors downstream of B. napus SRK that are absent in Arabidopsis species.
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the molecular and cellular regulation of brassicaceae Self Incompatibility and Self pollen rejection
International Review of Cell and Molecular Biology, 2019Co-Authors: Eli Jany, Hayley Nelles, Daphne R. GoringAbstract:Abstract In flowering plants, sexual reproduction is actively regulated by cell–cell communication between the male pollen and female pistil, and many species possess Self-Incompatibility systems for the selective rejection of Self-pollen to maintain genetic diversity. The Brassicaceae Self-Incompatibility pathway acts early on when pollen grains have landed on the stigmatic papillae at the top of the pistil. Extensive studies have revealed that Self-pollen rejection in the Brassicaceae is initiated by an S-haplotype–specific interaction between two polymorphic proteins: the pollen S-locus protein 11/S cysteine-rich (SP11/SCR) ligand and the stigma S receptor kinase (SRK). While the different S-haplotypes are typically codominant, there are several examples of dominant–recessive interactions, and a small RNA-based regulation of SP11/SCR expression has been uncovered as a mechanism behind these genetic interactions. Recent research has also added to our understanding of various cellular components in the pathway leading from the SP11/SCR–SRK interaction, including two signaling proteins, the M-locus protein kinase (MLPK) and the ARM-repeat containing 1 (ARC1) E3 ligase, as well as calcium fluxes and induction of autophagy in the stigmatic papillae. Finally, a better understanding of the compatible pollen responses that are targeted by the Self-Incompatibility pathway is starting to emerge, and this will allow us to more fully understand how the Brassicaceae Self-Incompatibility pathway causes Self-pollen rejection. Here, we provide an overview of the field, highlighting recent contributions to our understanding of Brassicaceae Self-Incompatibility, and draw comparisons to a recently discovered unilateral Incompatibility system.
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Mechanisms of Self-Incompatibility in flowering plants.
Cellular and Molecular Life Sciences, 2001Co-Authors: Nancy F. Silva, Daphne R. GoringAbstract:Self-Incompatibility is a widespread mechanism in flowering plants that prevents inbreeding and promotes outcrossing. The Self-Incompatibility response is genetically controlled by one or more multi-allelic loci, and relies on a series of complex cellular interactions between the Self-incompatible pollen and pistil. Although Self-Incompatibility functions ultimately to prevent Self-fertilization, flowering plants have evolved several unique mechanisms for rejecting the Self-incompatible pollen. The Self-Incompatibility system in the Solanaceae makes use of a multi-allelic RNase in the pistil to block incompatible pollen tube growth. In contrast, the Papaveraceae system appears to have complex cellular responses such as calcium fluxes, actin rearrangements, and programmed cell death occurring in the incompatible pollen tube. Finally, the Brassicaceae system has a receptor kinase signalling pathway activated in the pistil leading to pollen rejection. This review highlights the recent advances made towards understanding the cellular mechanisms involved in these Self-Incompatibility systems and discusses the striking differences between these systems.
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The molecular biology of Self-Incompatibility systems in flowering plants
Plant Cell Tissue and Organ Culture, 2001Co-Authors: Sophia L. Stone, Daphne R. GoringAbstract:Self-Incompatibility is a common mechanism by which flowering plants can exert some control over the process of fertilization. Typically, the Self-Incompatibility response involves the recognition and rejection of Self-incompatible pollen which leads to a block in Self-fertilization and, as a consequence, promotes outcrossing. In recent years, considerable progress has been made in the molecular understanding of several Self-Incompatibility systems. Interestingly, a common mechanism for Self-Incompatibility is not employed by all flowering plants, but in fact quite diverse mechanisms have been recruited for the rejection of Self-incompatible pollen. In this review, the recent advances in the Self-Incompatibility systems of the Solanaceae, Papaveraceae , and Brassicaceae will be described as well as some of the molecular work that is emerging for the Poaceae and the heteromorphic Self-Incompatibility systems.
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The Search for Components of the Self-Incompatibility Signalling Pathway(s) in Brassica napus
Annals of Botany, 2000Co-Authors: Daphne R. GoringAbstract:The Brassica Self-Incompatibility system is controlled by a multi-allelic S receptor kinase (SRK) gene. Upon contact between Self-incompatible pollen and the stigmatic papillae at the surface of the pistil, this receptor kinase is predicted to initiate a signalling pathway in the stigmatic papilla leading to the rejection of the Self-incompatible pollen. Several different approaches have been taken to determine the molecular events occurring in the stigmatic papillae upon activation of the Self-incompatible response. Examination of cytosolic calcium levels, electrical responses, cytoskeletal organization, and callose deposition in the stigmatic papillae during compatible and incompatible pollinations fail to reveal any responses specific to Self-Incompatibility. However, the identification of stigmatic proteins which interact with the SRK kinase domain has led to the characterization of a novel protein called ARC1 which appears to be a substrate for the S receptor kinase and is a positive effector of the Self-Incompatibility response.
Adrienne E. Clarke - One of the best experts on this subject based on the ideXlab platform.
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Self-Incompatibility in flowering plants
Current Opinion in Genetics & Development, 1995Co-Authors: John F. Golz, Adrienne E. Clarke, Ed NewbiginAbstract:Fertilization in flowering plants begins with a pollen grain bearing the male gametes landing on the female stigma. Several mechanisms enable the stigma to discriminate between the different types of pollen that it may receive, of which the best studied is Self-Incompatibility. The molecules that regulate Self-Incompatibility are well characterized in two plant families, the Solanaceae and Brassicaceae. This list has recently been extended to include candidates for Self-Incompatibility molecules from the Rosaceae, Papaveraceae and Poaceae. The information provided by the sequences of these molecules gives insight into the mechanisms and evolution of Self-Incompatibility in the different families of flowering plants.
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Self-Incompatibility: how plants avoid illegitimate offspring
Proceedings of the National Academy of Sciences of the United States of America, 1994Co-Authors: Daniel P. Matton, Adrienne E. Clarke, Norbert Nass, Ed NewbiginAbstract:Abstract In some families of flowering plants, a single Self-Incompatibility (S) locus prevents the fertilization of flowers by pollen from the same plant. Self-Incompatibility of this type involves the interaction of molecules produced by the S locus in pollen with those present in the female tissues (pistil). Until recently, the pistil products of the S locus were known in only two families, the Brassicaceae (which includes the cabbages and mustards) and Solanaceae (potatoes and tomatoes). A paper in this issue of the Proceedings describes the molecules associated with Self-Incompatibility in a third family, the Papaveraceae (poppies). We review current research on Self-Incompatibility in these three families and discuss the implications of the latest findings in poppy on the likely evolution of Self-Incompatibility in flowering plants. We also compare research into Self-Incompatibility with recent progress in understanding the mechanisms by which plants overcome infection by certain pathogens.
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Self Incompatibility in nicotiana alata involves degradation of pollen rrna
Nature, 1990Co-Authors: Bruce Mcclure, Marilyn A. Anderson, Julie E Gray, Adrienne E. ClarkeAbstract:GAMETOPHYTIC Self-Incompatibility is a genetically based system of cellular recognition in plants1. It prevents fertilization by pollen bearing an S-allele identical to either of the two S-alleles present in the female sporophytic tissues. Self-Incompatibility in the Solanaceae has been especially well studied and several S-allele specific style glycoproteins identified2–6. In addition, complementary DNAs for nine style S-glycoproteins have been sequenced7–10 and have homology with two fungal ribonucleases. Recently five Nicotiana alata S-glycoproteins were shown to be RNases (S-RNases)11. We now report that S-allele specific degradation of pollen RNA occurs in vivo. After incompatible, but not after compatible pollinations, pollen RNA becomes degraded. This specificity cannot be demonstrated in vitro using isolated S-RNases and pollen RNAs. Our results support a model in which the gametophytic Self-Incompatibility system in N. alata acts through a cytotoxic mechanism directed against pollen RNA.
Kent E Holsinger - One of the best experts on this subject based on the ideXlab platform.
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s rnase mediated gametophytic Self Incompatibility is ancestral in eudicots
Molecular Biology and Evolution, 2002Co-Authors: J E Steinbachs, Kent E HolsingerAbstract:: The evolutionary relationship between Self-Incompatibility systems in different families of flowering plants has long been a topic of interest. Physiological differences in the mode of gene action and the enormous sequence differences between genes with different modes of action suggest that many instances of Self-Incompatibility have arisen independently. In contrast, previous analyses of the S-RNase associated with gametophytic Self-Incompatibility in the eudicot families (Solanaceae, Scrophulariaceae, and Rosaceae) have suggested that sequences within families form well-supported and distinct lineages. In this study we demonstrate that in fact, S-RNase-mediated gametophytic Self-Incompatibility evolved only once in the eudicots.
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S-RNase–mediated Gametophytic Self-Incompatibility is Ancestral in Eudicots
Molecular Biology and Evolution, 2002Co-Authors: J E Steinbachs, Kent E HolsingerAbstract:: The evolutionary relationship between Self-Incompatibility systems in different families of flowering plants has long been a topic of interest. Physiological differences in the mode of gene action and the enormous sequence differences between genes with different modes of action suggest that many instances of Self-Incompatibility have arisen independently. In contrast, previous analyses of the S-RNase associated with gametophytic Self-Incompatibility in the eudicot families (Solanaceae, Scrophulariaceae, and Rosaceae) have suggested that sequences within families form well-supported and distinct lineages. In this study we demonstrate that in fact, S-RNase-mediated gametophytic Self-Incompatibility evolved only once in the eudicots.
Bruce Mcclure - One of the best experts on this subject based on the ideXlab platform.
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Plant Reproduction: Self-Incompatibility to Go.
Current Biology, 2016Co-Authors: Alejandro Tovar-mendez, Bruce McclureAbstract:In a new study, the Papaver rhoeas (poppy family) Self-Incompatibility system has been transferred into Arabidopsis thaliana, a distantly related plant with a very different floral structure. The simple poppy Self-Incompatibility system may finally make it possible to introduce this potentially valuable trait into any plant.
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Molecular genetics of Self-Incompatibility in Nicotiana alata.
Angiosperm Pollen and Ovules, 1992Co-Authors: Antony Bacic, Bruce Mcclure, Jane Murfett, Marilyn A. Anderson, Adrienne Elizabeth ClarkeAbstract:Self-Incompatibility is a genetically controlled mechanism which prevents inbreeding in plants (de Nettancourt, 1977). In many, but not all cases, it is controlled by a multi-allelic, single gene, the S-gene. The system operates to enhance outcrossing and to ensure that a plant is fertilized by a genetically distinct individual of the same species. There are two major types of Self-Incompatibility. The most widespread is gametophytic Self-Incompatibility which involves interaction of a product of the haploid genome of the male gametophyte (carried within the pollen grain) and a product of the diploid genome of the female tissue of the sporophyte, the pistil. In incompatible matings, as is the case when the S-allele carried by the haploid pollen matches either of the S-alleles present in the diploid style, pollen tube growth is arrested within the transmitting tract (Figure 1).
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Self Incompatibility in nicotiana alata involves degradation of pollen rrna
Nature, 1990Co-Authors: Bruce Mcclure, Marilyn A. Anderson, Julie E Gray, Adrienne E. ClarkeAbstract:GAMETOPHYTIC Self-Incompatibility is a genetically based system of cellular recognition in plants1. It prevents fertilization by pollen bearing an S-allele identical to either of the two S-alleles present in the female sporophytic tissues. Self-Incompatibility in the Solanaceae has been especially well studied and several S-allele specific style glycoproteins identified2–6. In addition, complementary DNAs for nine style S-glycoproteins have been sequenced7–10 and have homology with two fungal ribonucleases. Recently five Nicotiana alata S-glycoproteins were shown to be RNases (S-RNases)11. We now report that S-allele specific degradation of pollen RNA occurs in vivo. After incompatible, but not after compatible pollinations, pollen RNA becomes degraded. This specificity cannot be demonstrated in vitro using isolated S-RNases and pollen RNAs. Our results support a model in which the gametophytic Self-Incompatibility system in N. alata acts through a cytotoxic mechanism directed against pollen RNA.