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Rudolf Hagemann - One of the best experts on this subject based on the ideXlab platform.
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Struktur und Funktion der genetischen Information in den Plastiden: III. Genetik, Chlorophylle und Photosyntheseverhalten der Plastommutante „Mrs. Pollock‟ und der Genmutante „Cloth of Gold‟ von Pelargonium zonale
Biochemie und Physiologie der Pflanzen, 2017Co-Authors: Falko Herrmann, Rudolf HagemannAbstract:Summary 1. The variety “Mrs. Pollock” of Pelargonium zonale (fig. 1) is a periclinal mesochimera of the constitution: L I green, L II yellow, L III green. Reciprocal crosses between “Mrs. Pollock” and the green variety “Trautlieb” demonstrate a biparental Extranuclear Inheritance of the character yellow-green. The F 1 consists of green, yellow-green variegated and yellow seedlings (Table 1). 2. In yellow-green variegated F 1-plants “mixed cells” (fig. 2) have been found containing two genetically different types of plastids, green plastids (“from Trautlieb”) and yellow plastids (from “Mrs. Pollock”). 3. The yellow cells of “Mrs. Pollock” thus represent a yellow plastid mutant (= plastom mutant). Its genetic designation is “Extranuclear: gilva-1”; its symbol is en: gil-1. 4. On the other hand, crosses between the periclinal chimera „Cloth of Gold‟ (fig. 4, 5) and “Trautlieb” show, that the yellow cells of “Cloth of Gold” are heterozygous for a dominant gene mutation of the Aurea type (Table 1). 5. Leaves and shoots containing only mutant “Mrs. Pollock”-plastids are able to grow green intensely under dim light; its chlorophyll content increases up to 41 % of the control (Table 2). Under normal light conditions the leaves bleach out. (This is also true for the yellow areas of the periclinal chimera.) 6. The greenish mutant plastids have an almost normal ratio of chlorophyll a/b (Table 2). However, the absorption maximum of the long-wave form of chlorophyll a has in vivo been shifted 3-4 nm towards shorter waves (fig. 8) in comparison to wild type plastids. 7. In spite of its chlorophyll content, mutant “Mrs. Pollock”-plastids cannot perform any photosynthesis (fig. 6, 7). 8. Young yellow leaves of the gene mutant “Cloth of Gold” (yellow component) have a lower chlorophyll content than the greenish plastid mutant. Moreover, the content of chlorophyll b is very low (Table 3). Nevertheless these leaves are photosynthetically active (Table 3). The absorption maximum of the long-wave form of chlorophyll a is normal in this mutant (fig. 9). 9. In our opinion, the shift of the absorption maximum of the long-wave form of chlorophyll a is — in accordance with our results from other mutants — a general characteristic of a defect of photosynthesis. 10. The comparison of the yellow leaves of the gene mutant “Cloth of Gold” and the greenish leaves of the plastid mutant “Mrs. Pollock” demonstrates, that the whole chlorophyll content of the mutant plastids would be sufficient for photosynthesis. Therefore, the plastid mutant seems to contain a specific block, which entirely inhibits photosynthesis. 11. Experiments are in progress to characterize this plastom-specific block.
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The foundation of Extranuclear Inheritance: plastid and mitochondrial genetics
Molecular Genetics and Genomics, 2010Co-Authors: Rudolf HagemannAbstract:In 1909 two papers by Correns and by Baur published in volume 1 of Zeitschrift für induktive Abstammungs- und Vererbungslehre (now Molecular Genetics and Genomics ) reported on the non-Mendelian Inheritance of chlorophyll deficiencies. These papers, reporting the very first cases of Extranuclear Inheritance, laid the foundation for a new field: non-Mendelian or Extranuclear genetics. Correns observed a purely maternal Inheritance (in Mirabilis ), whereas Baur found a biparental Inheritance (in Pelargonium ). Correns suspected the non-Mendelian factors in the cytoplasm, while Baur believed that the plastids carry these Extranuclear factors. In the following years, Baur’s hypothesis was proved to be correct. Baur subsequently developed the theory of plastid Inheritance. In many genera the plastids are transmitted only uniparentally by the mother, while in a few genera there is a biparental plastid Inheritance. Commonly there is random sorting of plastids during ontogenetic development. Renner and Schwemmle as well as geneticists in other countries added additional details to this theory. Pioneering studies on mitochondrial Inheritance in yeast started in 1949 in the group of Ephrussi and Slonimski; respiration-deficient cells (petites in yeast, poky in Neurospora ) were demonstrated to be due to mitochondrial mutations. Electron microscopical and biochemical studies (1962–1964) showed that plastids and mitochondria contain organelle-specific DNA molecules. These findings laid the molecular basis for the two branches of Extranuclear Inheritance: plastid and mitochondrial genetics.
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Extranuclear Inheritance plastid genetics manipulation of plastid genomes and biotechnological applications
2000Co-Authors: Ralph Bock, Rudolf HagemannAbstract:When Erwin Baur, at the beginning of this century, proposed that the non-Mendelian Inheritance of leaf variegations can be explained with the assumption that chloroplasts (plastids) contain their own genetic information (Baur 1909, 1910), he found himself confronted with the sheer disbelief of many of his colleagues (Hagemann 1999). It took more than half a century until the discovery of chloroplast DNA (Chun et al. 1963; Sager and Ishida 1963) provided the ultimate proof for Baur’s ingenious hypothesis. Already with the very first analyses on chloroplast DNA sequences, it became obvious that plastid and eubacterial genomes are evolutionarily related (Schwarz and Kossel 1979, 1980), a finding that provided direct molecular evidence for the endosymbiotic origin of organelles (Gray 1989). The elucidation of the complete DNA sequence of two chloroplast genomes in 1986 (Ohyama et al. 1986; Shinozaki et al. 1986) marks a milestone in organelle genetics and has had a profound influence on our understanding of the biology and evolution of plastids (cf. Hagemann and Hagemann 1994; Hagemann et al. 1996, 1998).
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genetic Extranuclear Inheritance plastid genetics
Progress in botany, 1998Co-Authors: Rudolf Hagemann, Monika Hagemann, Ralph BlockAbstract:This chapter is a continuation of our chapter in Progress in Botany 57 (1996) and the previous articles in Volumes 47, 49, 51 and 55. In this chapter, we shall first report on the results of the complete sequencing of the plastid DNAs of several algae representing different taxa and shall work out the remarkable differences in the information content of these plastid genomes as compared with the coding capacity of the plastid DNAs of land plants which were dealt with in the previous volumes of Progress in Botany. Secondly, we will discuss recent results from genetic and molecular studies that have provided novel insights into the regulation of plastid gene expression and its interaction with the gene expression system in the nucleocytoplasmic compartment.
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Extranuclear Inheritance plastid genetics
Progress in botany, 1994Co-Authors: M M Hagemann, Rudolf Hagemann, Ralph BockAbstract:This review is a continuation of our chapter in Progress in Botany 55 (1994) and the previous articles in Volumes 47, 49, 51.
E. F. Legner - One of the best experts on this subject based on the ideXlab platform.
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Recombinant males in the parasitic waspMuscidifurax raptorellus [Hymenoptera: pteromalidae]
Biocontrol, 1991Co-Authors: E. F. LegnerAbstract:The identification of recombinant males inMuscidifurax raptorellus Kogan & Legner, secured from virgin hybrid ♀♀ formed by crossing cohorts from solitary and gregarious, populations, supports chromosomal Inheritance of gregarious oviposition behavior. Examination of parasitization behavior in female progeny that had recombinant male fathers, indicated the, existence of recombinant ♂♂. Such ♂♂ also were able to elicit immediate phenotypic changes in their female mating partners, at intensities expected from their genetic character, as previously observed with original parental ♂♂ in this species. Progeny originating from F1 mothers and recombinant fathers demonstrated the highest levels of heterosis, as measured by increased parasitization rates and numbers of eggs laid. Although Extranuclear Inheritance has not been eliminated, its influence on phenotypic changes in progeny seems minimal.
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Recombinant males in the parasitic waspMuscidifurax raptorellus [Hymenoptera: pteromalidae]
Entomophaga, 1991Co-Authors: E. F. LegnerAbstract:L'identification de ♂♂ recombinants de Muscidifurax raptorellus Kogan & Legner , issus de ♀♀ vierges descendantes de croisements entre populations grégaires et solitaires, a permis la mise à jour d'un déterminisme génétique chromosomique du comportement de grégarité. L'analyse de ce comportement dans la descendance de femelles croisées avec ces ♂♂ recombinants indique également la présence de tels ♂♂. Ces ♂♂ présentent de plus la capacité de provoquer des changements phénotypiques immédiats chez leur partenaire sexuel, et ce avec une intensité en accord avec leurs caractéristiques génétiques, comme ceci a pu être observé chez les ♂♂ de la souche parentale. La descendance issue de croisements entre ♀♀ F1 et ♂♂ recombinants présente un niveau élevé d'hétérosis se traduisant, par une augmentation à la fois du taux de parasitisme et du nombre d'œufs pondus. Bien que l'existence d'un déterminisme extra-chromosomique n'ait pu être écartée; son éventuelle influence sur le phénotype de la descendance semble limité. The identification of recombinant males in Muscidifurax raptorellus Kogan & Legner, secured from virgin hybrid ♀♀ formed by crossing cohorts from solitary and gregarious, populations, supports chromosomal Inheritance of gregarious oviposition behavior. Examination of parasitization behavior in female progeny that had recombinant male fathers, indicated the, existence of recombinant ♂♂. Such ♂♂ also were able to elicit immediate phenotypic changes in their female mating partners, at intensities expected from their genetic character, as previously observed with original parental ♂♂ in this species. Progeny originating from F_1 mothers and recombinant fathers demonstrated the highest levels of heterosis, as measured by increased parasitization rates and numbers of eggs laid. Although Extranuclear Inheritance has not been eliminated, its influence on phenotypic changes in progeny seems minimal.
Ralph Bock - One of the best experts on this subject based on the ideXlab platform.
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Extranuclear Inheritance plastid nuclear cooperation in photosystem i assembly in photosynthetic eukaryotes
2008Co-Authors: Mark Aurel Schottler, Ralph BockAbstract:Photosystem I (PSI), the final complex of the photosynthetic electron transport chain, is composed of at least 15 protein subunits. PSI accumulation is tightly regulated with approximately constant PSI amounts being present under all environ- mental and developmental conditions. Only about one-third of the PSI subunits is encoded in the plastid genome, the other two-thirds are nucleus-encoded, made in the cytosol and post-translationally imported into the chloroplast. In higher plants, the nucleus-encoded subunits must be distributed to dozens or hundreds of chloroplasts per
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Extranuclear Inheritance gene transfer out of plastids
2006Co-Authors: Ralph BockAbstract:Clearly, the evolution of the eukaryotic cell fulfills all three criteria: it involved the association of smaller independently replicating entities to form a larger whole by combining altogether three organisms and their genomes in one and the same cell (Fig. 1). In an endosymbiosis-like process, the preeukaryotic host successively engulfed two symbionts: an α-proteobacterium that gave rise to mitochondria and a cyanobacterium that gave rise to plastids. The endosymbiotic uptake of the two eubacterial cells was followed by the gradual integration of the endosymbionts into the metabolism of the host cell by establishing a division of labor and inventing sophisticated regulatory networks to co-ordinate the host’s gene expression with that of the endosymbionts. This process was accompanied by a drastic restructuring of all three genomes (Fig. 1) and involved (i) the loss of dispensable genetic information (such as genes for bacterial cell wall biosynthesis), (ii) the elimination of redundant genetic information (for example, genes for amino acid biosyntheses present in all three genomes), (iii) the acquisition of new gene functions to co-ordinate gene expression and metabolism in the three genetic compartments (for example, by establishing new signal transduction chains), and (iv) the massive translocation of genetic information between the three genomes (Fig. 1; Martin and Herrmann 1998). The main direction of this
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Extranuclear Inheritance chloroplast proteomics
2004Co-Authors: Michael Hippler, Ralph BockAbstract:Biology has arrived in the “omics” age. Currently, there is no better justification for the importance of one’s own research field than adding the suffix “omics” to it (Fig. 1). This somewhat unfortunate tendency was initiated with the systematic and high-throughput sequencing of entire genomes for which the term “genomics” was coined. Soon, researchers using systematic approaches to elucidate gene functions felt it important to distinguish between “structural genomics” (i.e. genome sequencing) and “functional genomics” (i.e. elucidation of gene functions; see e.g. Bock and Hippler 2002). What are the criteria for “omics”? Certainly, any “omics” should (1) take a systematic approach and (2) use high-throughput techniques with the ultimate goal of achieving completeness (complete sequence, complete set of RNAs, proteins, metabolites, etc.). From this viewpoint, clearly, some fields are relatively far (e.g. “metabolomics”) or even very far (e.g. “structuromics”) from meeting these criteria and, here, enthusiastic addition of the ending “omics” appears premature (Fig. 1). Open image in new window Fig. 1. The world of “omics” in modern biology
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Extranuclear Inheritance functional genomics in chloroplasts
2002Co-Authors: Ralph Bock, Michael HipplerAbstract:Over the last two decades, our knowledge about essentially all aspects of modern biology has benefited immensely from the huge amount of data generated by rapidly progressing genome projects. As organellar DNAs can easily be purified and are of a relatively small size, they were among the first targets of genome projects. The complete sequences of two chlo-roplast genomes (of the liverwort Marchantia polymorpha and the an-giosperm plant Nicotiana tabacum) were determined as early as in 1986 (Ohyama et al. 1986; Shinozaki et al. 1986). Up to now, more than a dozen chloroplast genome projects have been completed, covering a wide range of phylogenetically diverse taxa.
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Extranuclear Inheritance plastid genetics manipulation of plastid genomes and biotechnological applications
2000Co-Authors: Ralph Bock, Rudolf HagemannAbstract:When Erwin Baur, at the beginning of this century, proposed that the non-Mendelian Inheritance of leaf variegations can be explained with the assumption that chloroplasts (plastids) contain their own genetic information (Baur 1909, 1910), he found himself confronted with the sheer disbelief of many of his colleagues (Hagemann 1999). It took more than half a century until the discovery of chloroplast DNA (Chun et al. 1963; Sager and Ishida 1963) provided the ultimate proof for Baur’s ingenious hypothesis. Already with the very first analyses on chloroplast DNA sequences, it became obvious that plastid and eubacterial genomes are evolutionarily related (Schwarz and Kossel 1979, 1980), a finding that provided direct molecular evidence for the endosymbiotic origin of organelles (Gray 1989). The elucidation of the complete DNA sequence of two chloroplast genomes in 1986 (Ohyama et al. 1986; Shinozaki et al. 1986) marks a milestone in organelle genetics and has had a profound influence on our understanding of the biology and evolution of plastids (cf. Hagemann and Hagemann 1994; Hagemann et al. 1996, 1998).
Springer-verlag Wien - One of the best experts on this subject based on the ideXlab platform.
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Comparative structure of the pollen in species ofPassiflora: insights from the pollen wall and cytoplasm contents
2020Co-Authors: Springer-verlag WienAbstract:Pollen grains of three Brazilian species of Passiflora(P. elegans, P. suberosaandP. haematostigma) belonging to different subgenera were studied with respect to the wall and cytoplasm. New data were obtained on pollen wall histochemistry, cytoplasm contents and orga- nelle Inheritance. The structure of the pollen wall layers differed in all the species;P. elegansshares characters with those found in other species from the same subgenus. The exine foot layer is structured and evident only inP. haemato- stigmaand is not structured inP. elegans. The pollen grains have pollenkitt with lipid components. The cytoplasm of the vegetative cell contains dissolved and non-dissolved polysaccharides. The generative cell contains plastids and mitochondria in all the species analyzed, and consequently has the potential for paternal or biparental Extranuclear Inheritance. Aspects of the evolution of the characters of the species are discussed in the light of a recent phylogeny of the group, with a focus on the three subgenera. KeywordsExine!Intine!Maternal!Paternal and biparental Inheritance!Mitochondria!Plastids
Jorge Ernesto Araujo Mariath - One of the best experts on this subject based on the ideXlab platform.
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Comparative structure of the pollen in species of Passiflora: insights from the pollen wall and cytoplasm contents
Plant Systematics and Evolution, 2014Co-Authors: Adriano Silvério, Jorge Ernesto Araujo MariathAbstract:Pollen grains of three Brazilian species of Passiflora ( P. elegans, P. suberosa and P. haematostigma ) belonging to different subgenera were studied with respect to the wall and cytoplasm. New data were obtained on pollen wall histochemistry, cytoplasm contents and organelle Inheritance. The structure of the pollen wall layers differed in all the species; P. elegans shares characters with those found in other species from the same subgenus. The exine foot layer is structured and evident only in P. haematostigma and is not structured in P. elegans . The pollen grains have pollenkitt with lipid components. The cytoplasm of the vegetative cell contains dissolved and non-dissolved polysaccharides. The generative cell contains plastids and mitochondria in all the species analyzed, and consequently has the potential for paternal or biparental Extranuclear Inheritance. Aspects of the evolution of the characters of the species are discussed in the light of a recent phylogeny of the group, with a focus on the three subgenera.
