{"title":"Localisation pattern of homogalacturonan and arabinogalactan proteins in developing ovules of the gymnosperm plant Larix decidua Mill.","authors":"Katarzyna Rafińska, Elżbieta Bednarska","doi":"10.1007/s00497-010-0154-8","DOIUrl":"https://doi.org/10.1007/s00497-010-0154-8","url":null,"abstract":"<p><p>We have identified and characterised the temporal and spatial distribution of the homogalacturonan (HG) and arabinogalactan proteins (AGP) epitopes that are recognised by the antibodies JIM5, JIM7, LM2, JIM4, JIM8 and JIM13 during ovule differentiation in Larix decidua Mill. The results obtained clearly show differences in the pattern of localisation of specific HG epitopes between generative and somatic cells of the ovule. Immunocytochemical studies revealed that the presence of low-esterified HG is characteristic only of the wall of megasporocyte and megaspores. In maturing female gametophytes, highly esterified HG was the main form present, and the central vacuole of free nuclear gametophytes was particularly rich in this category of HG. This pool will probably be used in cell wall building during cellularisation. The selective labelling obtained with AGP antibodies indicates that some AGPs can be used as markers for gametophytic and sporophytic cells differentiation. Our results demonstrated that the AGPs recognised by JIM4 may constitute molecules determining changes in ovule cell development programs. Just after the end of meiosis, the signal detected with JIM4 labelling appeared only in functional and degenerating megaspores. This suggests that the antigens bound by JIM4 are involved in the initiation of female gametogenesis in L. decidua. Moreover, the analysis of AGPs distribution showed that differentiation of the nucellus cells occurs in the very young ovule stage before megasporogenesis. Throughout the period of ovule development, the pattern of localisation of the studied AGPs was different both in tapetum cells surrounding the gametophyte and in nucellus cells. Changes in the distribution of AGPs were also observed in the nucellus of the mature ovule, and they could represent an indicator of tissue arrangement to interact with the growing pollen tube. The possible role of AGPs in fertilisation is also discussed.</p>","PeriodicalId":21770,"journal":{"name":"Sexual Plant Reproduction","volume":"24 1","pages":"75-87"},"PeriodicalIF":0.0,"publicationDate":"2011-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00497-010-0154-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"29463214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Selective microspore abortion correlated with aneuploidy: an indication of meiotic drive.","authors":"Carol A Furness, Paula J Rudall","doi":"10.1007/s00497-010-0150-z","DOIUrl":"https://doi.org/10.1007/s00497-010-0150-z","url":null,"abstract":"<p><p>Selective megaspore abortion (monomegaspory) probably arose once in seed plants and occurs routinely in more than 70% of angiosperm species, representing one of the key characters of a heterosporous life history. In contrast, selective microspore abortion leading to pollen dispersal as pseudomonads (here termed monomicrospory) apparently arose at least twice independently within angiosperms, though it occurs in a limited number of taxa. Remarkably, similar examples of monomicrospory occur in members of two distantly related angiosperm families: the sedge family (Cyperaceae) and the epacrid subfamily (Styphelioideae) of the eudicot family Ericaceae. In sedges, monomicrospory is derived directly from normal tetrads, whereas epacrid pseudomonads apparently evolved via an intermediate stage, in which variable sterility occurs in a single tetrad. Our comparison of these two examples of selective microspore abortion highlights a correlation with aneuploidy, indicating that non-random chromosome segregation caused by monomicrospory could drive chromosomal mutations to rapid fixation through meiotic drive.</p>","PeriodicalId":21770,"journal":{"name":"Sexual Plant Reproduction","volume":"24 1","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2011-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00497-010-0150-z","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"29315501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anna Krahulcová, František Krahulec, Radka Rosenbaumová
{"title":"Expressivity of apomixis in 2n + n hybrids from an apomictic and a sexual parent: insights into variation detected in Pilosella (Asteraceae: Lactuceae).","authors":"Anna Krahulcová, František Krahulec, Radka Rosenbaumová","doi":"10.1007/s00497-010-0152-x","DOIUrl":"https://doi.org/10.1007/s00497-010-0152-x","url":null,"abstract":"<p><p>Reproductive variation was studied in the tetraploid Pilosella aurantiaca, hexaploid P. rubra (both species with facultative autonomous apospory) and in their 2n + n hybrids, which were obtained by crossing with a sexual pollen parent (tetraploid P. officinarum). The different DNA content in P. aurantiaca and P. officinarum demonstrated the actual 2n + n origin, both spontaneous from the field and through experimental crosses, of their hexaploid hybrids. The octoploid 2n + n progeny were recovered from an experimental cross of P. rubra and P. officinarum. The reproductive pathways operating in two maternal facultatively apomictic species and in the hybrids were quantified using a flow cytometric analysis of seeds obtained from either open-pollinated or emasculated plants. Whereas both maternal species displayed a high penetrance of apomixis, the level of apomixis among the majority of 2n + n hybrids was much lower and variable. Some of the hexaploid hybrids had a reduced seed set. Compared to the respective maternal parents, the decrease in apomixis due to haploid parthenogenesis and/or n + n mating was evident in almost all unreduced hybrids, irrespective of their field/experimental origin and ploidy. Hence, the reproductive behaviour in the apomictic maternal parent was profoundly different from that of the 2n + n hybrids with a sexual parent in spite of the preservation of the complete maternal genome in the hybrids. The regulatory interactions in hybrid genomes, such as effects of modifiers, heterochrony, and epigenetic control, may be consistent with the different expressivity of apomixis observed under different genetic backgrounds.</p>","PeriodicalId":21770,"journal":{"name":"Sexual Plant Reproduction","volume":"24 1","pages":"63-74"},"PeriodicalIF":0.0,"publicationDate":"2011-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00497-010-0152-x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"29385107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G Galla, G Barcaccia, A Schallau, M Puente Molins, H Bäumlein, T F Sharbel
{"title":"The cytohistological basis of apospory in Hypericum perforatum L.","authors":"G Galla, G Barcaccia, A Schallau, M Puente Molins, H Bäumlein, T F Sharbel","doi":"10.1007/s00497-010-0147-7","DOIUrl":"https://doi.org/10.1007/s00497-010-0147-7","url":null,"abstract":"<p><p>St. John's wort (Hypericum perforatum L., 2n = 4x = 32) is a medicinal plant that produces pharmaceutically important metabolites with antidepressive, anticancer and antiviral activities. It is also regarded as a serious weed in many countries. H. perforatum is furthermore an attractive model system for the study of apomixis. Natural populations of H. perforatum are predominantly composed of tetraploid individuals, although diploids and hexaploids are known to occur. It has been demonstrated that while diploids are sexual, polyploids are facultative apomictic whereby a single individual can produce both sexual and apomictic seeds. Despite our increasing understanding of gamete formation in sexually reproducing species, relatively little is known regarding the cytological basis of reproduction in H. perforatum. Here, we have studied embryo sac formation and the genetic constitution of seeds by means of staining-clearing of ovules/ovaries, DIC microscopy and flow cytometric seed screening (FCSS) of embryo and endosperm DNA contents. Comparisons of female sporogenesis and gametogenesis between sexual and apomictic accessions have enabled the identification of major phenotypic differences in embryo sac formation, in addition to complex fertilization scenarios entailing reduced and unreduced male and female gametes. These data provide new insights into the production of aposporous seeds in H. perforatum, and complement ongoing population genetic, genomic and transcriptomic studies.</p>","PeriodicalId":21770,"journal":{"name":"Sexual Plant Reproduction","volume":"24 1","pages":"47-61"},"PeriodicalIF":0.0,"publicationDate":"2011-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00497-010-0147-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"29096440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ján A Miernyk, Anna Preťová, Adela Olmedilla, Katarína Klubicová, Bohuš Obert, Martin Hajduch
{"title":"Using proteomics to study sexual reproduction in angiosperms.","authors":"Ján A Miernyk, Anna Preťová, Adela Olmedilla, Katarína Klubicová, Bohuš Obert, Martin Hajduch","doi":"10.1007/s00497-010-0149-5","DOIUrl":"https://doi.org/10.1007/s00497-010-0149-5","url":null,"abstract":"<p><p>While a relative latecomer to the postgenomics era of functional biology, the application of mass spectrometry-based proteomic analysis has increased exponentially over the past 10 years. Some of this increase is the result of transition of chemists, physicists, and mathematicians to the study of biology, and some is due to improved methods, increased instrument sensitivity, and better techniques of bioinformatics-based data analysis. Proteomic Biological processes are typically studied in isolation, and seldom are efforts made to coordinate results obtained using structural, biochemical, and molecular-genetic strategies. Mass spectrometry-based proteomic analysis can serve as a platform to bridge these disparate results and to additionally incorporate both temporal and anatomical considerations. Recently, proteomic analyses have transcended their initial purely descriptive applications and are being employed extensively in studies of posttranslational protein modifications, protein interactions, and control of metabolic networks. Herein, we provide a brief introduction to sample preparation, comparison of gel-based versus gel-free methods, and explanation of data analysis emphasizing plant reproductive applications. We critically review the results from the relatively small number of extant proteomics-based analyses of angiosperm reproduction, from flowers to seedlings, and speculate on the utility of this strategy for future developments and directions.</p>","PeriodicalId":21770,"journal":{"name":"Sexual Plant Reproduction","volume":" ","pages":"9-22"},"PeriodicalIF":0.0,"publicationDate":"2011-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00497-010-0149-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40060688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nick Fenby, Hong Pu, Roger Pennell, Uta Praekelt, Rob Day, Rod Scott
{"title":"An uncoupling screen for autonomous embryo mutants in Arabidopsis thaliana.","authors":"Nick Fenby, Hong Pu, Roger Pennell, Uta Praekelt, Rob Day, Rod Scott","doi":"10.1007/s00497-010-0142-z","DOIUrl":"https://doi.org/10.1007/s00497-010-0142-z","url":null,"abstract":"<p><p>Simple de novo screens in Arabidopsis thaliana have previously identified mutants that affect endosperm development but viable-embryo mutants have not been identified. Our strategy to identify autonomous embryo development was to uncouple embryo and endosperm fertilisation. This involved a male-sterile mutant population being crossed with a distinct pollen parent--the pollen was needed to initiate endosperm development and because it was distinct, the maternal progeny could be selected from the hybrid population. This process was refined over three stages, resulting in a viable approach to screen for autonomous embryo mutants. From 8,000 screened plants, a mutation was isolated in which the integument cells extended from the ovule and proliferated into a second complete twinned ovule. Some embryos from the mutant were normal but others developed fused cotyledons. In addition, a proportion of the progeny lacked paternal genes.</p>","PeriodicalId":21770,"journal":{"name":"Sexual Plant Reproduction","volume":"23 4","pages":"255-64"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00497-010-0142-z","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28975400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sangam L Dwivedi, Enrico Perotti, Hari D Upadhyaya, Rodomiro Ortiz
{"title":"Sexual and apomictic plant reproduction in the genomics era: exploring the mechanisms potentially useful in crop plants.","authors":"Sangam L Dwivedi, Enrico Perotti, Hari D Upadhyaya, Rodomiro Ortiz","doi":"10.1007/s00497-010-0144-x","DOIUrl":"https://doi.org/10.1007/s00497-010-0144-x","url":null,"abstract":"<p><p>Arabidopsis, Mimulus and tomato have emerged as model plants in researching genetic and molecular basis of differences in mating systems. Variations in floral traits and loss of self-incompatibility have been associated with mating system differences in crops. Genomics research has advanced considerably, both in model and crop plants, which may provide opportunities to modify breeding systems as evidenced in Arabidopsis and tomato. Mating system, however, not recombination per se, has greater effect on the level of polymorphism. Generating targeted recombination remains one of the most important factors for crop genetic enhancement. Asexual reproduction through seeds or apomixis, by producing maternal clones, presents a tremendous potential for agriculture. Although believed to be under simple genetic control, recent research has revealed that apomixis results as a consequence of the deregulation of the timing of sexual events rather than being the product of specific apomixis genes. Further, forward genetic studies in Arabidopsis have permitted the isolation of novel genes reported to control meiosis I and II entry. Mutations in these genes trigger the production of unreduced or apomeiotic megagametes and are an important step toward understanding and engineering apomixis.</p>","PeriodicalId":21770,"journal":{"name":"Sexual Plant Reproduction","volume":"23 4","pages":"265-79"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00497-010-0144-x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"29020427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Reduction in the critical dark length for flower induction during aging in the short-day plant Pharbitis nil var. Kidachi.","authors":"Hiroshi Hasegawa, Mizuki Yamada, Yuiko Iwase, Kaede C Wada, Kiyotoshi Takeno","doi":"10.1007/s00497-010-0139-7","DOIUrl":"https://doi.org/10.1007/s00497-010-0139-7","url":null,"abstract":"<p><p>The stress-sensitive short-day plant Pharbitis nil var. Kidachi flowers under a 16-h light and 8-h dark regime and non-stress conditions when grown for long periods of time. Such flowering was found to occur from the third week, and the floral buds were formed from the eighth node of the main stem. When young plants were grafted onto aged plants, the scions were induced to flower early. This flower induction by grafting was more effective when older plants were used as rootstocks. Grafting experiments using a single leaf as a donor revealed that younger leaves are more responsive to flower induction, suggesting that this age-mediated flowering response is not induced by aging or senescence of individual leaves. Rather, the plant may obtain the ability to flower as the whole plant ages. Flowering does not occur under continuous light conditions. A night break given in the 8-h dark period inhibits flowering. These results suggest that 8-h dark conditions, which are normally considered to be long-day conditions, actually correspond to short-day conditions for this plant. The 8-h dark conditions caused early flowering more efficiently in older plants. The critical dark length determined by a single treatment was 12 h in 0-week-old plants and was reduced to 6 h in 2- and 4-week-old plants. These results suggest that the critical dark length becomes shorter when plants get older. The expression of PnFT1 and PnFT2, orthologs of the flowering gene flowering locus T, was analyzed by reverse transcription-polymerase chain reaction revealing that the expression of PnFT at the end of dark period is correlated with flowering.</p>","PeriodicalId":21770,"journal":{"name":"Sexual Plant Reproduction","volume":"23 4","pages":"291-300"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00497-010-0139-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28849082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The osmotic property and fluorescent tracer movement of developing orchid embryos of Phaius tankervilliae (Aiton) Bl.","authors":"Yung-I Lee, Edward C Yeung","doi":"10.1007/s00497-010-0143-y","DOIUrl":"https://doi.org/10.1007/s00497-010-0143-y","url":null,"abstract":"<p><p>The suspensor plays an active role during the early embryo development of flowering plants. In orchids, the suspensor cells are highly vacuolated without structural specializations, and the possible mechanism(s) that enable the suspensor to serve as the nutrient uptake site is virtually unknown. Here, we used the fluorescent tracer CFDA to characterize the pathway for symplastic transport in the suspensor cells of developing embryos and to provide direct visual evidence that the orchid suspensor has unique physiological properties. The embryo proper uptakes the fluorescent dye through the suspensor. CF could first be detected throughout the suspensor cell and then subsequently in the embryo proper. A plasmolysis experiment clearly indicates that suspensor cells have a more negative osmotic potential than the adjoining testa cells. It is proposed that the preferential entry of CFDA into the suspensor cell of the Nun orchid is aided by the more negative osmotic potential of the suspensor than neighboring cells, providing a driving force for the uptake of water from the apoplast into the symplast.</p>","PeriodicalId":21770,"journal":{"name":"Sexual Plant Reproduction","volume":"23 4","pages":"337-41"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00497-010-0143-y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28984625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Susana Manzano, Cecilia Martínez, Pedro Gómez, Dolores Garrido, Manuel Jamilena
{"title":"Cloning and characterisation of two CTR1-like genes in Cucurbita pepo: regulation of their expression during male and female flower development.","authors":"Susana Manzano, Cecilia Martínez, Pedro Gómez, Dolores Garrido, Manuel Jamilena","doi":"10.1007/s00497-010-0140-1","DOIUrl":"https://doi.org/10.1007/s00497-010-0140-1","url":null,"abstract":"<p><p>Ethylene is an essential regulator of flower development in Cucurbita pepo, controlling the sexual expression, and the differentiation and maturation of floral organs. To study the action mechanism of ethylene during the male and female flower development, we have identified two CTR1 homologues from C. pepo, CpCTR1 and CpCTR2, and analysed their expressions during female and male flower development and in response to external treatments with ethylene. CpCTR1 and CpCTR2 share a high homology with plant CTR1-like kinases, but differ from other related kinases such as the Arabidopsis EDR1 and the tomato LeCTR2. The C-terminal ends of both CpCTR1 and CpCTR2 have all the conserved motifs of Ser/Thr kinase domains, including the ATP-binding signature and the protein kinase active site consensus sequence, which suggests that CpCTR1 and CpCTR2 could have the same function as CTR1 in ethylene signalling. The transcripts of both genes were detected in different organs of the plant, including roots, leaves and shoots, but were mostly accumulated in mature flowers. During the development of male and female flowers, CpCTR1 and CpCTR2 expressions were concomitant with ethylene production, which indicates that both genes could be upregulated by ethylene, at least in flowers. Moreover, external treatments with ethylene, although did not alter the expression of these two genes in seedlings and leaves, were able to upregulate their expression in flowers. In the earlier stages of flower development, when ethylene production is very low, the expression of CpCTR1 and CpCTR2 is higher in male floral organs, which agrees with the role of these genes as negative regulators of ethylene signalling, and explain the lower ethylene sensitivity of male flowers in comparison with female flowers. The function of the upregulation of these two genes in later stages of female flower development, when the production of ethylene is also increased, is discussed.</p>","PeriodicalId":21770,"journal":{"name":"Sexual Plant Reproduction","volume":"23 4","pages":"301-13"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00497-010-0140-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"28922741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}