• MeSH
• Chloroplasts analysis   MeSH
• Extrachromosomal Inheritance * MeSH
• Infertility genetics   MeSH
• DNA, Circular analysis   MeSH
• Humans MeSH
• DNA, Mitochondrial analysis   MeSH
• Models, Genetic * MeSH
• Plants genetics   MeSH
• Base Sequence MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH
• Names of Substances
• DNA, Circular MeSH
• DNA, Mitochondrial MeSH

Hybridization associated with polyploidization and apomixis is a frequent mechanism of speciation. Sorbus is a genus with ongoing hybridization resulting in a polyploid complex with different parental lineage. Triparens is the smallest hybridogenous subgenus of Sorbus so far known to comprise only two taxa, S. intermedia and S. × liljeforsii that combine the genomes of three taxa (S. aria agg., S. aucuparia and S. torminalis). To elucidate the origins of S. dacica, S. paxiana and S. tauricola, three new trigenomic candidates formerly believed to be of biparental origin with either S. aria agg. × S. aucuparia or S. aria agg. × S. torminalis lineage we combined data from HPLC and chloroplast DNA analysing additional 33 related taxa as well. We concluded that the 'torminalis-type' flavonoid profile and the 'aucuparia-type' plastid indicate the participation of both S. torminalis and S. aucuparia resulting in the formation of S. dacica, S. paxiana and S. tauricola. Sorbus aria agg. as the third ancestor and as a necessary link to meet genes of S. torminalis and S. aucuparia in one genome is obvious from morphological features (densely tomentose undersides of leaves). The tetraploid cytotypes and obligate pseudogamy of S. dacica and S. paxiana were determined by flow cytometry and are published here for the first time. The most probable evolutionary scenario for Triparens species is: 1. a diploid sexual S. aucuparia as pollen acceptor hybridized with a tetraploid apomictic taxon from the S. aria agg. producing a triploid apomictic taxon with 'aucuparia-type' plastid inherited maternally; 2. during a second crossing event this subgenus Soraria hybrid as maternal progenitor hybridized with the sexual diploid S. torminalis (providing gene(s) of apigenin O-glucuronide synthesis) forming a tetraploid Triparens hybrid with 'aucuparia-type' plastid and 'torminalis-type' flavonoids.

• Keywords
• Chloroplast inheritance, Flavonoids, Multiple origin, Polyploidy, Pseudogamy, Sorbus subg. Triparens, Taxonomy, Triparental hybridization,
• MeSH
• Hybridization, Genetic * MeSH
• Sorbus chemistry   classification   genetics   MeSH
• Tetraploidy MeSH
• Genetic Speciation * MeSH
• Publication type
• Journal Article MeSH

The Hieracium and Pilosella (Lactuceae, Asteraceae) genera of closely related hawkweeds contain species with two different modes of gametophytic apomixis (asexual seed formation). Both genera contain polyploid species, and in wild populations, sexual and apomictic species co-exist. Apomixis is known to co-exist with sexuality in apomictic Pilosella individuals, however, apomictic Hieracium have been regarded as obligate apomicts. Here, a developmental analysis of apomixis within 16 Hieracium species revealed meiosis and megaspore tetrad formation in 1 to 7% of ovules, for the first time indicating residual sexuality in this genus. Molecular markers linked to the two independent, dominant loci LOSS OF APOMEIOSIS (LOA) and LOSS OF PARTHENOGENESIS (LOP) controlling apomixis in Pilosella piloselloides subsp. praealta were screened across 20 phenotyped Hieracium individuals from natural populations, and 65 phenotyped Pilosella individuals from natural and experimental cross populations, to examine their conservation, inheritance and association with reproductive modes. All of the tested LOA and LOP-linked markers were absent in the 20 Hieracium samples irrespective of their reproductive mode. Within Pilosella, LOA and LOP-linked markers were essentially absent within the sexual plants, although they were not conserved in all apomictic individuals. Both loci appeared to be inherited independently, and evidence for additional genetic factors influencing quantitative expression of LOA and LOP was obtained. Collectively, these data suggest independent evolution of apomixis in Hieracium and Pilosella and are discussed with respect to current knowledge of the evolution of apomixis.

• MeSH
• Apomixis genetics   MeSH
• Asteraceae genetics   MeSH
• Biological Evolution * MeSH
• DNA, Chloroplast genetics   MeSH
• DNA, Plant genetics   MeSH
• Genetic Loci * MeSH
• Genetic Markers MeSH
• Haplotypes MeSH
• Conserved Sequence MeSH
• Molecular Sequence Data MeSH
• Genetics, Population MeSH
• Gene Expression Regulation, Plant MeSH
• Genes, Plant * MeSH
• Seeds genetics   MeSH
• Inheritance Patterns MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• DNA, Chloroplast MeSH
• DNA, Plant MeSH
• Genetic Markers MeSH

Gene flow between species may last a long time in plants. Reticulation inevitably causes difficulties in phylogenetic reconstruction. In this study, we looked into the genetic divergence and phylogeny of 20 Lilium species based on multilocus analyses of 8 genes of chloroplast DNA (cpDNA), the internally transcribed nuclear ribosomal DNA (nrITS) spacer and 20 loci extracted from the expressed sequence tag (EST) libraries of L. longiflorum Thunb. and L. formosanum Wallace. The phylogeny based on the combined data of the maternally inherited cpDNA and nrITS was largely consistent with the taxonomy of Lilium sections. This phylogeny was deemed the hypothetical species tree and uncovered three groups, i.e., Cluster A consisting of 4 taxa from the sections Pseudolirium and Liriotypus, Cluster B consisting of the 4 taxa from the sections Leucolirion, Archelirion and Daurolirion, and Cluster C comprising 10 taxa mostly from the sections Martagon and Sinomartagon. In contrast, systematic inconsistency occurred across the EST loci, with up to 19 genes (95%) displaying tree topologies deviating from the hypothetical species tree. The phylogenetic incongruence was likely attributable to the frequent genetic exchanges between species/sections, as indicated by the high levels of genetic recombination and the IMa analyses with the EST loci. Nevertheless, multilocus analysis could provide complementary information among the loci on the species split and the extent of gene flow between the species. In conclusion, this study not only detected frequent gene flow among Lilium sections that resulted in phylogenetic incongruence but also reconstructed a hypothetical species tree that gave insights into the nature of the complex relationships among Lilium species.

• MeSH
• DNA, Chloroplast genetics   MeSH
• Phylogeny MeSH
• Lilium classification   genetics   MeSH
• Genes, Plant * MeSH
• Gene Flow * MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• DNA, Chloroplast MeSH

Numerous temperate plants now distributed across Eurasia are hypothesized to have originated and migrated from the Qinghai-Tibet Plateau (QTP) and adjacent regions. However, this hypothesis has never been tested through a phylogeographic analysis of a widely distributed species. Here, we use Hippophaë rhamnoides as a model to test this hypothesis. We collected 635 individuals from 63 populations of the nine subspecies of H. rhamnoides. We sequenced two maternally inherited chloroplast (cp) DNA fragments and also the bi-paternally inherited nuclear ribosomal ITS. We recovered five major clades in phylogenetic trees constructed from cpDNA and internal transcribed spacer (ITS) sequence variation. Most sampled individuals of six subspecies that are distributed in northern China, central Asia and Asia Minor/Europe, respectively, comprised monophyletic clades (or subclades) nested within those found in the QTP. Two subspecies in the QTP were paraphyletic, while the placement of another subspecies from the Mongolian Plateau differed between the ITS and cpDNA phylogenetic trees. Our phylogeographic analyses supported an 'out-of-QTP' hypothesis for H. rhamnoides followed by allopatric divergence, hybridization and introgression. These findings highlight the complexity of intraspecific evolutions and the importance of the QTP as a center of origin for many temperate plants.

• MeSH
• DNA, Chloroplast * MeSH
• Elaeagnaceae genetics   MeSH
• Phylogeny * MeSH
• Phylogeography * MeSH
• Hybridization, Genetic MeSH
• DNA, Intergenic MeSH
• Seed Dispersal MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Tibet MeSH
• Names of Substances
• DNA, Chloroplast * MeSH
• DNA, Intergenic MeSH

BACKGROUND AND AIMS: Molecular evidence for natural primary hybrids composed of three different plant species is very rarely reported. An investigation was therefore carried out into the origin and a possible scenario for the rise of a sterile plant clone showing a combination of diagnostic morphological features of three separate, well-defined Potamogeton species. METHODS: The combination of sequences from maternally inherited cytoplasmic (rpl20-rps12) and biparentally inherited nuclear ribosomal DNA (ITS) was used to identify the exact identity of the putative triple hybrid. KEY RESULTS: Direct sequencing showed ITS variants of three parental taxa, P. gramineus, P. lucens and P. perfoliatus, whereas chloroplast DNA identified P. perfoliatus as the female parent. A scenario for the rise of the triple hybrid through a fertile binary hybrid P. gramineus x P. lucens crossed with P. perfoliatus is described. CONCLUSIONS: Even though the triple hybrid is sterile, it possesses an efficient strategy for its existence and became locally successful even in the parental environment, perhaps as a result of heterosis. The population investigated is the only one known of this hybrid, P. x torssanderi, worldwide. Isozyme analysis indicated the colony to be genetically uniform. The plants studied represented a single clone that seems to have persisted at this site for a long time.

• MeSH
• DNA, Chloroplast chemistry   genetics   MeSH
• DNA, Plant chemistry   genetics   MeSH
• Species Specificity MeSH
• Hybridization, Genetic genetics   MeSH
• Magnoliopsida genetics   growth & development   MeSH
• Molecular Sequence Data MeSH
• Base Sequence MeSH
• Sequence Analysis, DNA MeSH
• Sequence Homology, Nucleic Acid MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• DNA, Chloroplast MeSH
• DNA, Plant MeSH

The origins and evolution of sub-Antarctic island floras are not well understood. In particular there is uncertainty about the ages of the contemporary floras and the ultimate origins of the lineages they contain. Pringlea R. Br. (Brassicaceae) is a monotypic genus endemic to four sub-Antarctic island groups in the southern Indian Ocean. Here we used sequences from both the chloroplast and nuclear genomes to examine the phylogenetic position of this enigmatic genus. Our analyses confirm that Pringlea falls within the tribe Thelypodieae and provide a preliminary view of its relationships within the group. Divergence time estimates and ancestral area reconstructions imply Pringlea diverged from a South American ancestor ~5 Myr ago. It remains unclear whether the ancestor of Pringlea dispersed directly to the South Indian Ocean Province (SIOP) or used Antarctica as a stepping-stone; what is clear, however, is that following arrival in the SIOP several additional long-distance dispersal events must be inferred to explain the current distribution of this species. Our analyses also suggest that although Pringlea is likely to have inherited cold tolerance from its closest relatives, the distinctive morphology of this species evolved only after it split from the South American lineage. More generally, our results lend support to the hypothesis that angiosperms persisted on the sub-Antarctic islands throughout the Pliocene and Pleistocene. Taken together with evidence from other sub-Antarctic island plant groups, they suggest the extant flora of sub-Antarctic is likely to have been assembled over a broad time period and from lineages with distinctive biogeographic histories.

• MeSH
• Bayes Theorem MeSH
• Brassicaceae classification   genetics   MeSH
• Cell Nucleus genetics   MeSH
• DNA, Chloroplast genetics   MeSH
• Phylogeny * MeSH
• Phylogeography MeSH
• Models, Genetic MeSH
• Evolution, Molecular * MeSH
• Islands MeSH
• Sequence Analysis, DNA MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Indian Ocean MeSH
• Islands MeSH
• Names of Substances
• DNA, Chloroplast MeSH

Sequenced genomic data for carnivorous plants are scarce, especially regarding the mitogenomes (MTs) and further studies are crucial to obtain a better understanding of the topic. In this study, we sequenced and characterized the mitochondrial genome of the tuberous carnivorous plant Genlisea tuberosa, being the first of its genus to be sequenced. The genome comprises 729,765 bp, encoding 80 identified genes of which 36 are protein-coding, 40 tRNA, four rRNA genes, and three pseudogenes. An intronic region from the cox1 gene was identified that encodes an endonuclease enzyme that is present in the other sequenced species of Lentibulariaceae. Chloroplast genes (pseudogene and complete) inserted in the MT genome were identified, showing possible horizontal transfer between organelles. In addition, 50 pairs of long repeats from 94 to 274 bp are present, possibly playing an important role in the maintenance of the MT genome. Phylogenetic analysis carried out with 34 coding mitochondrial genes corroborated the positioning of the species listed here within the family. The molecular dynamism in the mitogenome (e.g. the loss or pseudogenization of genes, insertion of foreign genes, the long repeats as well as accumulated mutations) may be reflections of the carnivorous lifestyle where a significant part of cellular energy was shifted for the adaptation of leaves into traps molding the mitochondrial DNA. The sequence and annotation of G. tuberosa's MT will be useful for further studies and serve as a model for evolutionary and taxonomic clarifications of the group as well as improving our comprehension of MT evolution.

• Keywords
• Carnivorous plants, Genomic evolution, Lentibulariaceae, Mitochondrial DNA,
• MeSH
• Phylogeny MeSH
• Genome, Mitochondrial * genetics   MeSH
• Lamiales * genetics   MeSH
• DNA, Mitochondrial MeSH
• Genes, Mitochondrial MeSH
• RNA, Transfer genetics   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• DNA, Mitochondrial MeSH
• RNA, Transfer MeSH

Current knowledge of the genetic mechanisms underlying the inheritance of photosynthetic activity in forest trees is generally limited, yet it is essential both for various practical forestry purposes and for better understanding of broader evolutionary mechanisms. In this study, we investigated genetic variation underlying selected chlorophyll a fluorescence (ChlF) parameters in structured populations of Scots pine (Pinus sylvestris L.) grown on two sites under non-stress conditions. These parameters were derived from the OJIP part of the ChlF kinetics curve and characterize individual parts of primary photosynthetic processes associated, for example, with the exciton trapping by light-harvesting antennae, energy utilization in photosystem II (PSII) reaction centers (RCs) and its transfer further down the photosynthetic electron-transport chain. An additive relationship matrix was estimated based on pedigree reconstruction, utilizing a set of highly polymorphic single sequence repeat markers. Variance decomposition was conducted using the animal genetic evaluation mixed-linear model. The majority of ChlF parameters in the analyzed pine populations showed significant additive genetic variation. Statistically significant heritability estimates were obtained for most ChlF indices, with the exception of DI0/RC, φD0 and φP0 (Fv/Fm) parameters. Estimated heritabilities varied around the value of 0.15 with the maximal value of 0.23 in the ET0/RC parameter, which indicates electron-transport flux from QA to QB per PSII RC. No significant correlation was found between these indices and selected growth traits. Moreover, no genotype × environment interaction (G × E) was detected, i.e., no differences in genotypes' performance between sites. The absence of significant G × E in our study is interesting, given the relatively low heritability found for the majority of parameters analyzed. Therefore, we infer that polygenic variability of these indices is selectively neutral.

• Keywords
• OJIP transient, pedigree reconstruction, photosynthesis,
• MeSH
• Pinus sylvestris genetics   physiology   MeSH
• Chlorophyll A MeSH
• Chlorophyll physiology   MeSH
• Fluorescence MeSH
• Photosynthetic Reaction Center Complex Proteins physiology   MeSH
• Photosynthesis genetics   MeSH
• Photosystem II Protein Complex physiology   MeSH
• Genetic Variation * MeSH
• Genotype * MeSH
• Quantitative Trait, Heritable * MeSH
• Forests MeSH
• Genes, Plant MeSH
• Trees genetics   physiology   MeSH
• Light MeSH
• Electron Transport MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Chlorophyll A MeSH
• Chlorophyll MeSH
• Photosynthetic Reaction Center Complex Proteins MeSH
• Photosystem II Protein Complex MeSH

BACKGROUND: Bacteria and mitochondria contain translocases that function to transport proteins across or insert proteins into their inner and outer membranes. Extant mitochondria retain some bacterial-derived translocases but have lost others. While BamA and YidC were integrated into general mitochondrial protein transport pathways (as Sam50 and Oxa1), the inner membrane TAT translocase, which uniquely transports folded proteins across the membrane, was retained sporadically across the eukaryote tree. RESULTS: We have identified mitochondrial TAT machinery in diverse eukaryotic lineages and define three different types of eukaryote-encoded TatABC-derived machineries (TatAC, TatBC and TatC-only). Here, we investigate TatAC and TatC-only machineries, which have not been studied previously. We show that mitochondria-encoded TatAC of the jakobid Andalucia godoyi represent the minimal functional pathway capable of substituting for the Escherichia coli TatABC complex and can transport at least one substrate. However, selected TatC-only machineries, from multiple eukaryotic lineages, were not capable of supporting the translocation of this substrate across the bacterial membrane. Despite the multiple losses of the TatC gene from the mitochondrial genome, the gene was never transferred to the cell nucleus. Although the major constraint preventing nuclear transfer of mitochondrial TatC is likely its high hydrophobicity, we show that in chloroplasts, such transfer of TatC was made possible due to modifications of the first transmembrane domain. CONCLUSIONS: At its origin, mitochondria inherited three inner membrane translocases Sec, TAT and Oxa1 (YidC) from its bacterial ancestor. Our work shows for the first time that mitochondrial TAT has likely retained its unique function of transporting folded proteins at least in those few eukaryotes with TatA and TatC subunits encoded in the mitochondrial genome. However, mitochondria, in contrast to chloroplasts, abandoned the machinery multiple times in evolution. The overall lower hydrophobicity of the Oxa1 protein was likely the main reason why this translocase was nearly universally retained in mitochondrial biogenesis pathways.

• Keywords
• Hydrophobicity, Mitochondrial evolution, Protein transport, TAT translocase,
• MeSH
• Escherichia coli genetics   MeSH
• Eukaryota genetics   MeSH
• Membrane Transport Proteins genetics   metabolism   MeSH
• Mitochondria metabolism   MeSH
• Evolution, Molecular * MeSH
• Escherichia coli Proteins chemistry   genetics   metabolism   MeSH
• Protein Transport MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Membrane Transport Proteins MeSH
• Escherichia coli Proteins MeSH