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S-Locus Genotyping in Japanese Plum by High Throughput Sequencing Using a Synthetic S-Loci Reference Sequence. Int J Mol Sci 2023; 24:ijms24043932. [PMID: 36835346 PMCID: PMC9960950 DOI: 10.3390/ijms24043932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/09/2023] [Accepted: 02/10/2023] [Indexed: 02/18/2023] Open
Abstract
Self-incompatibility in Prunus species is governed by a single locus consisting of two highly multi-allelic and tightly linked genes, one coding for an F-box protein-i.e., SFB in Prunus- controlling the pollen specificity and one coding for an S-RNase gene controlling the pistil specificity. Genotyping the allelic combination in a fruit tree species is an essential procedure both for cross-based breeding and for establishing pollination requirements. Gel-based PCR techniques using primer pairs designed from conserved regions and spanning polymorphic intronic regions are traditionally used for this task. However, with the great advance of massive sequencing techniques and the lowering of sequencing costs, new genotyping-by-sequencing procedures are emerging. The alignment of resequenced individuals to reference genomes, commonly used for polymorphism detection, yields little or no coverage in the S-locus region due to high polymorphism between different alleles within the same species, and cannot be used for this purpose. Using the available sequences of Japanese plum S-loci concatenated in a rosary-like structure as synthetic reference sequence, we describe a procedure to accurately genotype resequenced individuals that allowed the analysis of the S-genotype in 88 Japanese plum cultivars, 74 of them are reported for the first time. In addition to unraveling two new S-alleles from published reference genomes, we identified at least two S-alleles in 74 cultivars. According to their S-allele composition, they were assigned to 22 incompatibility groups, including nine new incompatibility groups reported here for the first time (XXVII-XXXV).
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Abdallah D, Baraket G, Perez V, Salhi Hannachi A, Hormaza JI. Self-compatibility in peach [ Prunus persica (L.) Batsch]: patterns of diversity surrounding the S-locus and analysis of SFB alleles. HORTICULTURE RESEARCH 2020; 7:170. [PMID: 33082976 PMCID: PMC7527504 DOI: 10.1038/s41438-020-00392-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/08/2020] [Accepted: 08/12/2020] [Indexed: 05/07/2023]
Abstract
Self-incompatibility (SI) to self-compatibility (SC) transition is one of the most frequent and prevalent evolutionary shifts in flowering plants. Prunus L. (Rosaceae) is a genus of over 200 species most of which exhibit a Gametophytic SI system. Peach [Prunus persica (L.) Batsch; 2n = 16] is one of the few exceptions in the genus known to be a fully self-compatible species. However, the evolutionary process of the complete and irreversible loss of SI in peach is not well understood and, in order to fill that gap, in this study 24 peach accessions were analyzed. Pollen tube growth was controlled in self-pollinated flowers to verify their self-compatible phenotypes. The linkage disequilibrium association between alleles at the S-locus and linked markers at the end of the sixth linkage group was not significant (P > 0.05), except with the closest markers suggesting the absence of a signature of negative frequency dependent selection at the S-locus. Analysis of SFB1 and SFB2 protein sequences allowed identifying the absence of some variable and hypervariable domains and the presence of additional α-helices at the C-termini. Molecular and evolutionary analysis of SFB nucleotide sequences showed a signature of purifying selection in SFB2, while the SFB1 seemed to evolve neutrally. Thus, our results show that the SFB2 allele diversified after P. persica and P. dulcis (almond) divergence, a period which is characterized by an important bottleneck, while SFB1 diversified at a transition time between the bottleneck and population expansion.
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Affiliation(s)
- Donia Abdallah
- Faculté des Sciences de Tunis, Département Biologie, Université de Tunis El Manar, 2092 Tunis, Tunisie
| | - Ghada Baraket
- Faculté des Sciences de Tunis, Département Biologie, Université de Tunis El Manar, 2092 Tunis, Tunisie
| | - Veronica Perez
- Laboratorio de Agrobiología Juan José Bravo Rodríguez (Cabildo Insular de La Palma), Unidad Técnica del Instituto de Productos Naturales y Agrobiología (IPNA-CSIC), 38700 S/C La Palma, Canary Islands, Spain
| | - Amel Salhi Hannachi
- Faculté des Sciences de Tunis, Département Biologie, Université de Tunis El Manar, 2092 Tunis, Tunisie
| | - Jose I. Hormaza
- Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora (IHSM La Mayora-UMA-CSIC), 29750 Algarrobo-Costa, Malaga Spain
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Abdallah D, Baraket G, Ben Mustapha S, Angeles Moreno MA, Salhi Hannachi A. Molecular and Evolutionary Characterization of Pollen S Determinant (SFB Alleles) in Four Diploid and Hexaploid Plum Species (Prunus spp.). Biochem Genet 2020; 59:42-61. [PMID: 32737642 DOI: 10.1007/s10528-020-09990-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 07/20/2020] [Indexed: 11/28/2022]
Abstract
In more than 60 families of angiosperms, the self- and cross-fertilization is avoided through a complex widespread genetic system called self-incompatibility (SI). One of the major puzzling issues concerning the SI is the evolution of this system in species with complex polyploid genomes. Among plums, one of the first fruits species to attract human interest, polyploid species represent enormous genetic potential, which can be exploited in breeding programs. However, molecular studies in these species are very scarce due to the complexity of their genome. In order to study the SFB gene [the male component of gametophytic self-incompatibility system (GSI)] in plum species, 36 plum accessions belonging to diploid and hexaploid species were used. A total of 19 different alleles were identified; 1 of them was revealed after analyzing sequences. Peptide sequence analysis allowed identifying the five domains features of the SFB gene. Polymorphism analysis showed a subtle difference between domesticated and open pollinated Tunisian accessions and suggested a probable influence of the ploidy level. Divergence analysis between studied sequences showed that a new specificity may appear after 5.3% of divergence at synonymous sites between pairs of sequences in Prunus insititia, 6% in Prunus cerasifera, 8% and 9% in Prunus domestica and Prunus salicina respectively. Furthermore, sites under positive selection, the ones more likely to be responsible for specificity determination, were identified. A positive and significant Pearson correlation was found between the divergence between sequences, divergence time, fixed substitutions (MK test), and PSS number. These results supported the model assuming that functionally distinct proteins have arisen not as a result of chance fixation of neutral variants, but rather as a result of positive Darwinian selection. Further, the role that plays recombination can not be ruled out, since a rate of 0.08 recombination event per polymorphic sites was identified.
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Affiliation(s)
- Donia Abdallah
- Département de Biologie, Faculté des Sciences de Tunis, Université de Tunis El Manar, Campus Universitaire El Manar, 2092, Tunis, Tunisia
| | - Ghada Baraket
- Département de Biologie, Faculté des Sciences de Tunis, Université de Tunis El Manar, Campus Universitaire El Manar, 2092, Tunis, Tunisia
| | - Sana Ben Mustapha
- Département de Biologie, Faculté des Sciences de Tunis, Université de Tunis El Manar, Campus Universitaire El Manar, 2092, Tunis, Tunisia
| | - Marı A Angeles Moreno
- Departamento de Pomologı́a, Estación Experimental de Aula Dei, CSIC, Apartado 13034, 50080, Saragossa, Spain
| | - Amel Salhi Hannachi
- Département de Biologie, Faculté des Sciences de Tunis, Université de Tunis El Manar, Campus Universitaire El Manar, 2092, Tunis, Tunisia.
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Muñoz-Sanz JV, Zuriaga E, Cruz-García F, McClure B, Romero C. Self-(In)compatibility Systems: Target Traits for Crop-Production, Plant Breeding, and Biotechnology. FRONTIERS IN PLANT SCIENCE 2020; 11:195. [PMID: 32265945 PMCID: PMC7098457 DOI: 10.3389/fpls.2020.00195] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 02/10/2020] [Indexed: 05/13/2023]
Abstract
Self-incompatibility (SI) mechanisms prevent self-fertilization in flowering plants based on specific discrimination between self- and non-self pollen. Since this trait promotes outcrossing and avoids inbreeding it is a widespread mechanism of controlling sexual plant reproduction. Growers and breeders have effectively exploited SI as a tool for manipulating domesticated crops for thousands of years. However, only within the past thirty years have studies begun to elucidate the underlying molecular features of SI. The specific S-determinants and some modifier factors controlling SI have been identified in the sporophytic system exhibited by Brassica species and in the two very distinct gametophytic systems present in Papaveraceae on one side and in Solanaceae, Rosaceae, and Plantaginaceae on the other. Molecular level studies have enabled SI to SC transitions (and vice versa) to be intentionally manipulated using marker assisted breeding and targeted approaches based on transgene integration, silencing, and more recently CRISPR knock-out of SI-related factors. These scientific advances have, in turn, provided a solid basis to implement new crop production and plant breeding practices. Applications of self-(in)compatibility include widely differing objectives such as crop yield and quality improvement, marker-assisted breeding through SI genotyping, and development of hybrids for overcoming intra- and interspecific reproductive barriers. Here, we review scientific progress as well as patented applications of SI, and also highlight future prospects including further elucidation of SI systems, deepening our understanding of SI-environment relationships, and new perspectives on plant self/non-self recognition.
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Affiliation(s)
| | - Elena Zuriaga
- Centro de Citricultura y Producción Vegetal, Instituto Valenciano de Investigaciones Agrarias (IVIA), Valencia, Spain
| | - Felipe Cruz-García
- Departmento de Bioquímica, Facultad de Química, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico
| | - Bruce McClure
- Department of Biochemistry, University of Missouri, Columbia, MO, United States
| | - Carlos Romero
- Instituto de Biología Molecular y Celular de Plantas (IBMCP), Consejo Superior de Investigaciones Científicas (CSIC)—Universitat Politécnica de València (UPV), Valencia, Spain
- *Correspondence: Carlos Romero,
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Abdallah D, Baraket G, Perez V, Ben Mustapha S, Salhi-Hannachi A, Hormaza JI. Analysis of Self-Incompatibility and Genetic Diversity in Diploid and Hexaploid Plum Genotypes. FRONTIERS IN PLANT SCIENCE 2019; 10:896. [PMID: 31354768 PMCID: PMC6640205 DOI: 10.3389/fpls.2019.00896] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 06/24/2019] [Indexed: 05/23/2023]
Abstract
During the last decade, S-genotyping has been extensively investigated in fruit tree crops such as those belonging to the Prunus genus, including plums. In plums, S-allele typing has been largely studied in diploid species but works are scarcer in polyploid species due to the complexity of the polyploid genome. This study was conducted in order to analyze the S-genotypes of 30 diploid P. salicina, 17 of them reported here for the first time, and 29 hexaploid plums (24 of P. domestica and 5 of P. insititia). PCR analysis allowed identifying nine S-alleles in the P. salicina samples allocating the 30 accessions in 16 incompatibility groups, two of them identified here for the first time. In addition, pollen tube growth was studied in self-pollinated flowers of 17 Tunisian P. salicina under the microscope. In 16 samples, including one carrying the Se allele, which has been correlated with self-compatibility, the pollen tubes were arrested in the style. Only in one cultivar ("Bedri"), the pollen tubes reached the base of the style. Twelve S-alleles were identified in the 24 P. domestica and 5 P. insititia accessions, assigning accessions in 16 S-genotypes. S-genotyping results were combined with nine SSR loci to analyze genetic diversity. Results showed a close genetic relationship between P. domestica and P. salicina and between P. domestica and P. insititia corroborating that S-locus genotyping is suitable for molecular fingerprinting in diploid and polyploid Prunus species.
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Affiliation(s)
- Donia Abdallah
- Laboratoire de Génétique Moléculaire, Immunologie et Biotechnologie, Faculté des Sciences de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Ghada Baraket
- Laboratoire de Génétique Moléculaire, Immunologie et Biotechnologie, Faculté des Sciences de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Veronica Perez
- Unidad Técnica del IPNA-CSIC, Laboratorio de Agrobiología Juan José Bravo Rodríguez (Cabildo Insular de La Palma), Santa Cruz de La Palma, Spain
| | - Sana Ben Mustapha
- Laboratoire de Génétique Moléculaire, Immunologie et Biotechnologie, Faculté des Sciences de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Amel Salhi-Hannachi
- Laboratoire de Génétique Moléculaire, Immunologie et Biotechnologie, Faculté des Sciences de Tunis, Université de Tunis El Manar, Tunis, Tunisia
| | - Jose I. Hormaza
- Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora (IHSM La Mayora -UMA-CSIC), Algarrobo, Spain
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Inheritance of hetero-diploid pollen S-haplotype in self-compatible tetraploid Chinese cherry (Prunus pseudocerasus Lindl). PLoS One 2013; 8:e61219. [PMID: 23596519 PMCID: PMC3626605 DOI: 10.1371/journal.pone.0061219] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 03/08/2013] [Indexed: 11/19/2022] Open
Abstract
The breakdown of self-incompatibility, which could result from the accumulation of non-functional S-haplotypes or competitive interaction between two different functional S-haplotypes, has been studied extensively at the molecular level in tetraploid Rosaceae species. In this study, two tetraploid Chinese cherry (Prunus pseudocerasus) cultivars and one diploid sweet cherry (Prunus avium) cultivar were used to investigate the ploidy of pollen grains and inheritance of pollen-S alleles. Genetic analysis of the S-genotypes of two intercross-pollinated progenies showed that the pollen grains derived from Chinese cherry cultivars were hetero-diploid, and that the two S-haplotypes were made up of every combination of two of the four possible S-haplotypes. Moreover, the distributions of single S-haplotypes expressed in self- and intercross-pollinated progenies were in disequilibrium. The number of individuals of the two different S-haplotypes was unequal in two self-pollinated and two intercross-pollinated progenies. Notably, the number of individuals containing two different S-haplotypes (S1- and S5-, S5- and S8-, S1- and S4-haplotype) was larger than that of other individuals in the two self-pollinated progenies, indicating that some of these hetero-diploid pollen grains may have the capability to inactivate stylar S-RNase inside the pollen tube and grow better into the ovaries.
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Wang CL, Zhang ZP, Tonosaki K, Kitashiba H, Nishio T. S genotyping in Japanese plum and sweet cherry by allele-specific hybridization using streptavidin-coated magnetic beads. PLANT CELL REPORTS 2013; 32:567-576. [PMID: 23338476 DOI: 10.1007/s00299-013-1388-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 01/07/2013] [Accepted: 01/07/2013] [Indexed: 06/01/2023]
Abstract
We report a rapid and reliable method for S genotyping of Rosaceae fruit trees, which would to be useful for successful planting of cross-compatible cultivars in orchards. Japanese plum (Prunus salicina) and sweet cherry (Prunus avium), belonging to the family Rosaceae, possess gametophytic self-incompatibility controlled by a single polymorphic locus containing at least two linked genes, S-RNase and SFB (S-haplotype-specific F-box gene). For successful planting of cross-compatible cultivars of Rosaceae fruit trees in commercial orchards, it is necessary to obtain information on S genotypes of cultivars. Recently, a method of dot-blot analysis utilizing allele-specific oligonucleotides having sequences of SFB-HVa region has been developed for identification of S haplotypes in Japanese plum and sweet cherry. However, dot-blot hybridization requires considerable time and skill for analysis even of a small number of plant samples. Thus, a quick and efficient method for S genotyping was developed in this study. In this method, instead of a nylon membrane used for dot-blot hybridization, streptavidin-coated magnetic beads are used to immobilize PCR products, which are hybridized with allele-specific oligonucleotide probes. Our improved method allowed us to identify 10 S haplotypes (S-a, S-b, S-c, S-d, S-e, S-f, S-h, S-k, S-7 and S-10) of 13 Japanese plum cultivars and 10 S haplotypes (S-1, S-2, S-3, S-4, S-4', S-5, S-6, S-7, S-9 and S-16) of 13 sweet cherry cultivars utilizing SFB or S-RNase gene polymorphism. This method would be suitable for identification of S genotypes of a small number of plant samples.
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Affiliation(s)
- Chun-Lei Wang
- Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai, Miyagi, 981-8555, Japan
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Wu J, Wang Z, Shi Z, Zhang S, Ming R, Zhu S, Khan MA, Tao S, Korban SS, Wang H, Chen NJ, Nishio T, Xu X, Cong L, Qi K, Huang X, Wang Y, Zhao X, Wu J, Deng C, Gou C, Zhou W, Yin H, Qin G, Sha Y, Tao Y, Chen H, Yang Y, Song Y, Zhan D, Wang J, Li L, Dai M, Gu C, Wang Y, Shi D, Wang X, Zhang H, Zeng L, Zheng D, Wang C, Chen M, Wang G, Xie L, Sovero V, Sha S, Huang W, Zhang S, Zhang M, Sun J, Xu L, Li Y, Liu X, Li Q, Shen J, Wang J, Paull RE, Bennetzen JL, Wang J, Zhang S. The genome of the pear (Pyrus bretschneideri Rehd.). Genome Res 2012; 23:396-408. [PMID: 23149293 PMCID: PMC3561880 DOI: 10.1101/gr.144311.112] [Citation(s) in RCA: 500] [Impact Index Per Article: 41.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The draft genome of the pear (Pyrus bretschneideri) using a combination of BAC-by-BAC and next-generation sequencing is reported. A 512.0-Mb sequence corresponding to 97.1% of the estimated genome size of this highly heterozygous species is assembled with 194× coverage. High-density genetic maps comprising 2005 SNP markers anchored 75.5% of the sequence to all 17 chromosomes. The pear genome encodes 42,812 protein-coding genes, and of these, ∼28.5% encode multiple isoforms. Repetitive sequences of 271.9 Mb in length, accounting for 53.1% of the pear genome, are identified. Simulation of eudicots to the ancestor of Rosaceae has reconstructed nine ancestral chromosomes. Pear and apple diverged from each other ∼5.4–21.5 million years ago, and a recent whole-genome duplication (WGD) event must have occurred 30–45 MYA prior to their divergence, but following divergence from strawberry. When compared with the apple genome sequence, size differences between the apple and pear genomes are confirmed mainly due to the presence of repetitive sequences predominantly contributed by transposable elements (TEs), while genic regions are similar in both species. Genes critical for self-incompatibility, lignified stone cells (a unique feature of pear fruit), sorbitol metabolism, and volatile compounds of fruit have also been identified. Multiple candidate SFB genes appear as tandem repeats in the S-locus region of pear; while lignin synthesis-related gene family expansion and highly expressed gene families of HCT, C3′H, and CCOMT contribute to high accumulation of both G-lignin and S-lignin. Moreover, alpha-linolenic acid metabolism is a key pathway for aroma in pear fruit.
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Affiliation(s)
- Jun Wu
- Centre of Pear Engineering Technology Research, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China
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Zhang SW, Huang GX, Ding F, He XH, Pan JC. Mechanism of seedlessness in a new lemon cultivar ‘Xiangshui’ [Citrus limon (L.) Burm. F.]. ACTA ACUST UNITED AC 2012; 25:337-45. [DOI: 10.1007/s00497-012-0201-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2012] [Accepted: 10/21/2012] [Indexed: 11/30/2022]
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Self-compatibility of 'Katy' apricot (Prunus armeniaca L.) is associated with pollen-part mutations. ACTA ACUST UNITED AC 2010; 24:23-35. [PMID: 20658154 DOI: 10.1007/s00497-010-0148-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Accepted: 07/05/2010] [Indexed: 10/19/2022]
Abstract
Apricot (Prunus armeniaca L.) cultivars originated in China display a typical S-RNase-based gametophytic self-incompatibility (GSI). 'Katy', a natural self-compatible cultivar belonging to the European ecotype group, was used as a useful material for breeding new cultivars with high frequency of self-compatibility by hybridizing with Chinese native cultivars. In this work, the pollen-S genes (S-haplotype-specific F-box gene, or SFB gene) of 'Katy' were first identified as SFB₁ and SFB (8), and the S-genotype was determined as S₁ S₈. Genetic analysis of 'Katy' progenies under controlled pollination revealed that the stylar S₁-RNase and S₈-RNase have a normal function in rejecting wild-type pollen with the same S-haplotype, while the pollen grains carrying either the SFB₁ or the SFB₈ gene are both able to overcome the incompatibility barrier. However, the observed segregation ratios of the S-genotype did not fit the expected ratios under the assumption that the pollen-part mutations are linked to the S-locus. Moreover, alterations in the SFB₁ and SFB₈ genes and pollen-S duplications were not detected. These results indicated that the breakdown of SI in 'Katy' occurred in pollen, and other factors not linked to the S-locus, which caused a loss of pollen S-activity. These findings support a hypothesis that modifying factors other than the S-locus are required for GSI in apricot.
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Wang CL, Xu GH, Jiang XT, Chen G, Wu J, Wu HQ, Zhang SL. S-RNase triggers mitochondrial alteration and DNA degradation in the incompatible pollen tube of Pyrus pyrifolia in vitro. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2009; 57:220-9. [PMID: 18786182 DOI: 10.1111/j.1365-313x.2008.03681.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Pear (Pyrus pyrifolia L.) has a S-RNase-based gametophytic self-incompatibility (SI) mechanism, and S-RNase has also been implicated in the rejection of self-pollen and genetically identical pollen. No studies, however, have examined the extent of organelle alterations during the SI response in Pyrus pyrifolia. Consequently, this study focused on the alterations to mitochondria and nuclear DNA in incompatible pollen tubes of the pear. Methylthiazolyldiphenyl-tetrazolium bromide was used to evaluate the viability of pollen tubes under S-RNase challenge. The results showed that the viability of the control and compatible pollen tubes decreased slightly, but that of the incompatible pollen and pollen tubes began to decline at 30 min. The mitochondrial membrane potential (Delta psi(mit)) was also tested with rhodamine 123 30 min after SI challenge, and was shown to have collapsed in the incompatible pollen tubes after exposure to S-RNase. Western blotting 2 h after SI challenge confirmed that the Delta psi(mit) collapse induced leakage of cytochrome c into the cytosol. Swollen mitochondria were detected by transmission electron microscopy as early as 1 h after SI challenge and the degradation of nuclear DNA was observed by both 4,6-diamidino-2-phenylindole and transferase-mediated dUTP nick-end labeling. These diagnostic features of programmed cell death (PCD) suggested that PCD may specifically occur in incompatible pollen tubes.
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Affiliation(s)
- Chun-Lei Wang
- Pear Engineering Research Center, Nanjing Agricultural University, Nanjing, Jiangsu, People's Republic of China
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Yamane H, Tao R. Molecular Basis of Self-(in)compatibility and Current Status of S-genotyping in Rosaceous Fruit Trees. ACTA ACUST UNITED AC 2009. [DOI: 10.2503/jjshs1.78.137] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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13
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Vieira J, Santos RAM, Habu T, Tao R, Vieira CP. The Prunus self-incompatibility locus (S locus) is seldom rearranged. J Hered 2008; 99:657-60. [PMID: 18703538 DOI: 10.1093/jhered/esn063] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Self-incompatibility enables flowering plants to discriminate between self- and non-selfpollen. In Prunus, the 2 genes determining specificity are the S-RNase (the female determinant that is a glycoprotein with ribonuclease activity) and the SFB (the male determinant, a protein with an F-box motif). In all Prunus S haplotypes characterized so far, with the exception of Prunus armeniaca S(2) haplotype, the 2 genes have opposite transcription orientations. Nevertheless, the relative transcription orientation observed in P. armeniaca S(2) haplotype has been postulated to be the one present in all S haplotypes from this species. We show that this is not the case by demonstrating that that the relative transcription orientation of the pollen and pistil genes of the P. armeniaca S(17) haplotype is that which is commonly found in Prunus. Using a phylogenetic approach, we show that the relative transcription orientation of the S-RNase and SFB genes is seldom changed (less than once every 380 million years). This contrasts with the Brassica sporophytic S locus where chromosomal rearrangements are often observed in the region between the pollen and pistil genes.
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Affiliation(s)
- Jorge Vieira
- Instituto de Biologia Molecular e Celular (IBMC), University of Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.
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14
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Huang SX, Wu HQ, Li YR, Wu J, Zhang SJ, Heng W, Zhang SL. Competitive interaction between two functional S-haplotypes confer self-compatibility on tetraploid Chinese cherry (Prunus pseudocerasus Lindl. CV. Nanjing Chuisi). PLANT CELL REPORTS 2008; 27:1075-85. [PMID: 18327590 DOI: 10.1007/s00299-008-0528-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2007] [Revised: 02/04/2008] [Accepted: 02/20/2008] [Indexed: 05/13/2023]
Abstract
Self-incompatibility (SI) has been studied extensively at the molecular level in Solanaceae, Rosaceae and Scrophulariaceae, all of which exhibit gametophytic self-incompatibility (GSI). In the present study, four PpsS-haplotypes (Prunus pseudocerasus S-haplotypes) comprising at least two genes, i.e., PpsS-RNase (P. pseudocerasus S-RNase) and PpsSFB (P. pseudocerasus S-haplotype-specific F-box) have been successfully isolated in tetraploid P. pseudocerasus Lindl. CV. Nanjing Chuisi ("NC") which exhibited self-compatibility (SC), and its S-genotype was determined as S-1/S-3'/S-5/S-7. These PpsS-RNases, which were expressed exclusively in style, shared the typical structural features with S-RNases from other Prunus species exhibiting GSI. All PpsSFBs showed similar structure characteristics of SFBs from other Prunus species, and matched with the necessary conditions for pollen S-determinant. No mutations leading to dysfunction of S-haplotype were found in their full-length c-DNA sequences, except for PpsS-3'-haplotype which was not amplified by PCR. These four S-haplotypes complied with tetrasomic inheritance. Diploid pollen grains with S-genotypes S-7/S-1, S-7/S-5 and S-1/S-5 can grow the full length of the style after self-pollination, while pollen grains with S-3'/S-7, S-3'/S-1 and S-3'/S-5 cannot. These results suggest that PpsS-haplotypes-1, -5 and -7 are functional, and that competitive interaction between two of them confer self-compatibility on cultivar "NC". Furthermore, in terms of recognition specificity, diploid pollen grains carrying PpsS-3'-haplotype are equal to monoploid pollen grains carrying the other functional S-haplotype.
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Affiliation(s)
- S-X Huang
- College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
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Liu ZQ, Xu GH, Zhang SL. Pyrus pyrifolia stylar S-RNase induces alterations in the actin cytoskeleton in self-pollen and tubes in vitro. PROTOPLASMA 2007; 232:61-67. [PMID: 18094928 DOI: 10.1007/s00709-007-0269-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Accepted: 03/31/2007] [Indexed: 05/25/2023]
Abstract
Pears (Pyrus pyrifolia L.) have an S-RNase-based gametophytic self-incompatibility system, and S-RNases have also been implicated in self-pollen or genetically identical pollen rejection. Tip growth of the pollen tube is dependent on a functioning actin cytoskeleton. In this study, configurations of the actin cytoskeleton in P. pyrifolia pollen and effects of stylar S-RNases on its dynamics were investigated by fluorescence and confocal microscopy. Results show that actin filaments in normal pollen grains exist in fusiform or circular structures. When the pollen germinates, actin filaments assembled around one of the germination pores, and then actin bundles oriented axially throughout the shank of the growing tube. There was a lack of actin filaments 5-15 microm from the tube tip. When self-stylar S-RNase was added to the basal medium, pollen germination and tube growth were inhibited. The configuration of the actin cytoskeleton changed throughout the culturing time: during the first 20 min, the actin configurations in the self-pollen and tube were similar to the control; after 20 min of treatment, the actin filaments in the pollen tube gradually moved into a network running from the shank to the tip; finally, there was punctate actin present throughout the whole tube. Although the actin filaments of the self-pollen grain also disintegrated into punctate foci, the change was slower than in the tube. Furthermore, the alterations to the actin cytoskeleton occurred prior to the arrest of pollen tube growth. These results suggest that P. pyrifolia stylar S-RNase induces alterations in the actin cytoskeleton in self-pollen grains and tubes.
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Affiliation(s)
- Zhu-Qin Liu
- College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu, People's Republic of China
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