The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Christoph Neinhuis - One of the best experts on this subject based on the ideXlab platform.
-
Evolution of Class II TCP genes in perianth bearing Piperales and their contribution to the bilateral calyx in Aristolochia.
The New phytologist, 2020Co-Authors: Natalia Pabón-mora, Stefan Wanke, Christoph Neinhuis, Barbara A. Ambrose, Yesenia Madrigal, Juan F. Alzate, Cristina Ferrándiz, Favio GonzalezAbstract:Controlled spatiotemporal cell division and expansion are responsible for floral bilateral symmetry. Genetic studies have pointed to class II TCP genes as major regulators of cell division and floral patterning in model core eudicots. Here we study their evolution in perianth-bearing Piperales and their expression in Aristolochia, a rare occurrence of bilateral perianth outside eudicots and monocots. The evolution of class II TCP genes reveals single-copy CYCLOIDEA-like genes and three paralogs of CINCINNATA (CIN) in early diverging angiosperms. All class II TCP genes have independently duplicated in Aristolochia subgenus Siphisia. Also CIN2 genes duplicated before the diversification of Saruma and Asarum. Sequence analysis shows that CIN1 and CIN3 share motifs with Cyclin proteins and CIN2 genes have lost the miRNA319a binding site. Expression analyses of all paralogs of class II TCP genes in Aristolochia fimbriata point to a role of CYC and CIN genes in maintaining differential perianth expansion during mid- and late flower developmental stages by promoting cell division in the distal and ventral portion of the limb. It is likely that class II TCP genes also contribute to cell division in the leaf, the gynoecium and the ovules in A. fimbriata.
-
Stem anatomy and the evolution of woodiness in Piperales
International Journal of Plant Sciences, 2015Co-Authors: Santiago Trueba Sanchez, Stefan Wanke, Sarah T. Wagner, Christoph Neinhuis, Nick P. Rowe, Sandrine IsnardAbstract:Premise of research. Piperales displays a wide diversity of growth forms that appears to be linked with differences in cambial activity and subsequent derived wood production. To date, no overall synthesis of the evolution of woodiness in Piperales has been done and few studies have proposed an ancestral habit (woody/herbaceous). We provide anatomical data of all lineages within Piperales and reconstruct ancestral character states, focusing on the origin of woodiness within the order and on the ecological significance of key anatomical features. Methodology. Stem anatomical observations with special emphasis on wood anatomical features were performed on 28 species of the Piperales; by combining previously published studies with original data, we conducted phylogenetic reconstructions of cambial activity and vessel element perforation plates to assess the origin of woodiness and vessel evolution in Piperales. Pivotal results. Different patterns of cambial activity are observed in Piperales, from active secondary growth in both intra- and interfascicular areas in Aristolochia, Thottea (Aristolochiaceae), Saruma (Asaraceae), Manekia, and Piper (Piperaceae) to cambial activity mainly restricted to fascicular areas in Saururaceae and a complete lack of secondary growth in Verhuellia. Vessels in Piperaceae, Aristolochiaceae, and Asaraceae present simple perforation plates, while those of Saururaceae are mostly scalariform. A stem endodermis bearing a Casparian band—an atypical feature in aerial stems—is reported for all genera within the Piperaceae and for Saururus and Houttuynia in the Saururaceae. Conclusions. The common ancestor of the order likely had an active cambium and woody habit, including vessel elements with simple perforation plates. All woody species share several wood features, including wide and tall rays, suggesting a single origin of wood in the order. The high diversity of growth forms observed in Piperales is linked to frequent shifts in cambial activity and changes in habit-related features within the different lineages
-
Stem Anatomy and the Evolution of Woodiness in Piperales
International Journal of Plant Sciences, 2015Co-Authors: Santiago Trueba, Stefan Wanke, Sarah T. Wagner, Christoph Neinhuis, Nick P. Rowe, Sandrine IsnardAbstract:Premise of research. Piperales displays a wide diversity of growth forms that appears to be linked with differences in cambial activity and subsequent derived wood production. To date, no overall s...
-
Major trends in stem anatomy and growth forms in the perianth-bearing Piperales, with special focus on Aristolochia.
Annals of Botany, 2014Co-Authors: Sarah T. Wagner, Marie-stéphanie Samain, Sandrine Isnard, Christoph Neinhuis, Erika Maass, Nick P. Rowe, Linnea Hesse, Jay Bolin, Stefan WankeAbstract:BACKGROUND AND AIMS: The order Piperales has the highest diversity of growth forms among the earliest angiosperm lineages, including trees, shrubs, climbers and herbs. However, within the perianth-bearing Piperales (Asarum, Saruma, Lactoris, Hydnora, Prosopanche, Thottea and Aristolochia), climbing species only occur in the most species-rich genus Aristolochia. This study traces anatomical and morphological traits among these lineages, to detect trends in growth form evolution and developmental processes. METHODS: Transverse stem sections of different developmental stages of representatives of Asarum, Saruma, Lactoris, Hydnora, Thottea and Aristolochia were compared and anatomical traits were linked to growth form evolution. Biomechanical properties of representative climbers were determined in three-point bending tests and are discussed based on the anatomical observations. Growth form evolution of the perianth-bearing Piperales was reconstructed by ancestral character state reconstruction using Mesquite. KEY RESULTS: While species of Asarum and Saruma are exclusively herbaceous, species of the remaining genera show a higher diversity of growth habit and anatomy. This growth form diversity is accompanied by a more complex stem anatomy and appropriate biomechanical properties. The ancestral growth form of the perianth-bearing Piperales is reconstructed with either a shrub-like or herbaceous character state, while the following three backbone nodes in the reconstruction show a shrub-like character state. Accordingly, the climbing habit most probably evolved in the ancestor of Aristolochia. CONCLUSIONS: Since the ancestor of the perianth-bearing Piperales has been reconstructed with a herb- or shrub-like habit, it is proposed that the climbing habit is a derived growth form, which evolved with the diversification of Aristolochia, and might have been a key feature for its diversification. Observed anatomical synapomorphies, such as the perivascular fibres in Lactoris, Thottea and Aristolochia, support the phylogenetic relationship of several lineages within the perianth-bearing Piperales. In addition, the hypothesis that the vegetative organs of the holoparasitic Hydnoraceae are most probably rhizomes is confirmed.
-
Relative substitution rates of nuclear single copy genes (nSCG) are elevated.
2013Co-Authors: Julia Naumann, Marie-stéphanie Samain, Lena Frenzke, Christoph Neinhuis, Karsten Salomo, Joshua P. Der, Eric K. Wafula, Jay F. Bolin, Erika Maass, Claude W. DepamphilisAbstract:The relative substitution rates are shown for five partitioned datasets representing major Piperales lineages. In general, nSCG contribute significantly to the overall rate of the 19-gene-matrix in the different Piperales lineages. Within Hydnoraceae, rates of nSCG regions are 2–3 fold greater than nuclear ribosomal DNA (nrDNA) or mitochondrial DNA (mtDNA). However, comparing the relative rate of Hydnoraceae with other Piperales, the nSCG regions do not exceed the rate of other photosynthetic member such as Verhuellioideae. The partition of nSCG for Piperales is reduced from 14 to the 8 most complete genes for these lineages. Rates were compared using GRate (http://bioinfweb.info/Software/GRate) for different Piperales lineages using Canellales (Canella) as the reference and all other sampled taxa as outgroups.
Stefan Wanke - One of the best experts on this subject based on the ideXlab platform.
-
Evolution of Class II TCP genes in perianth bearing Piperales and their contribution to the bilateral calyx in Aristolochia.
The New phytologist, 2020Co-Authors: Natalia Pabón-mora, Stefan Wanke, Christoph Neinhuis, Barbara A. Ambrose, Yesenia Madrigal, Juan F. Alzate, Cristina Ferrándiz, Favio GonzalezAbstract:Controlled spatiotemporal cell division and expansion are responsible for floral bilateral symmetry. Genetic studies have pointed to class II TCP genes as major regulators of cell division and floral patterning in model core eudicots. Here we study their evolution in perianth-bearing Piperales and their expression in Aristolochia, a rare occurrence of bilateral perianth outside eudicots and monocots. The evolution of class II TCP genes reveals single-copy CYCLOIDEA-like genes and three paralogs of CINCINNATA (CIN) in early diverging angiosperms. All class II TCP genes have independently duplicated in Aristolochia subgenus Siphisia. Also CIN2 genes duplicated before the diversification of Saruma and Asarum. Sequence analysis shows that CIN1 and CIN3 share motifs with Cyclin proteins and CIN2 genes have lost the miRNA319a binding site. Expression analyses of all paralogs of class II TCP genes in Aristolochia fimbriata point to a role of CYC and CIN genes in maintaining differential perianth expansion during mid- and late flower developmental stages by promoting cell division in the distal and ventral portion of the limb. It is likely that class II TCP genes also contribute to cell division in the leaf, the gynoecium and the ovules in A. fimbriata.
-
Peruvian Window-Leaved Peperomia Taxa Display Unique Crystal Macropatterns in High-Altitude Environments
International Journal of Plant Sciences, 2017Co-Authors: Harry T Horner, Stefan Wanke, Birgit Oelschlägel, Marie-stéphanie SamainAbstract:Premise of research. Window-leaved Peperomia taxa (WPs) occur in the Peruvian Andes from near sea level to high altitudes and display curled leaves that are generally exposed to high irradiance and periodic drought, far different from the typically uncurled humid-forest, often-shaded Peperomia taxa. Even though representatives of the latter taxa, as well as other members of the Piperales, have been observed for the presence (type) and location (macropattern) of leaf crystals in previous studies, this special group of WP taxa has missed scrutiny. It was important to determine whether the WP taxa contained the same types of crystals in the same tissue locations and, if not, what any differences could be that are related to their anatomy, environment, and physiology.Methodology. Living leaves of 35 available accessions from the 42 currently recognized taxa of WPs were chemically fixed, some cleared and/or vibratome sectioned or fractured to observe the internal leaf tissues for the presence of crystals compo...
-
Stem anatomy and the evolution of woodiness in Piperales
International Journal of Plant Sciences, 2015Co-Authors: Santiago Trueba Sanchez, Stefan Wanke, Sarah T. Wagner, Christoph Neinhuis, Nick P. Rowe, Sandrine IsnardAbstract:Premise of research. Piperales displays a wide diversity of growth forms that appears to be linked with differences in cambial activity and subsequent derived wood production. To date, no overall synthesis of the evolution of woodiness in Piperales has been done and few studies have proposed an ancestral habit (woody/herbaceous). We provide anatomical data of all lineages within Piperales and reconstruct ancestral character states, focusing on the origin of woodiness within the order and on the ecological significance of key anatomical features. Methodology. Stem anatomical observations with special emphasis on wood anatomical features were performed on 28 species of the Piperales; by combining previously published studies with original data, we conducted phylogenetic reconstructions of cambial activity and vessel element perforation plates to assess the origin of woodiness and vessel evolution in Piperales. Pivotal results. Different patterns of cambial activity are observed in Piperales, from active secondary growth in both intra- and interfascicular areas in Aristolochia, Thottea (Aristolochiaceae), Saruma (Asaraceae), Manekia, and Piper (Piperaceae) to cambial activity mainly restricted to fascicular areas in Saururaceae and a complete lack of secondary growth in Verhuellia. Vessels in Piperaceae, Aristolochiaceae, and Asaraceae present simple perforation plates, while those of Saururaceae are mostly scalariform. A stem endodermis bearing a Casparian band—an atypical feature in aerial stems—is reported for all genera within the Piperaceae and for Saururus and Houttuynia in the Saururaceae. Conclusions. The common ancestor of the order likely had an active cambium and woody habit, including vessel elements with simple perforation plates. All woody species share several wood features, including wide and tall rays, suggesting a single origin of wood in the order. The high diversity of growth forms observed in Piperales is linked to frequent shifts in cambial activity and changes in habit-related features within the different lineages
-
Towards uncovering evolution of lineage-specific calcium oxalate crystal patterns in Piperales
Botany, 2015Co-Authors: Harry T Horner, Marie-stéphanie Samain, Sarah T. Wagner, Stefan WankeAbstract:Piperales is among the largest and most diverse angiosperm orders (>4000 species), occurring broadly in tropical and temperate habitats. Twenty-four of the species from 12 genera, representing all lineages of Piperales, except the holoparasitic Hydnoraceae, display a mixture of leaf calcium oxalate crystal types found in previous studies of the two genera of Piperaceae subfamily Piperoideae (Peperomia Ruiz & Pav. and Piper L.). Crystal macropatterns, a result of varying leaf anatomies and diverse habitats, are investigated in a comparative way by using clearings and recent molecular phylogenetic hypotheses to trace crystal types and macropattern evolution. Ancestral character reconstruction reveals that the most recent common ancestor of Piperales had either crystal sand or druses or both and that prisms, raphides, and styloids are derived from the ancestral crystal type(s). These results are also recovered for both the ancestors of the perianth-less and the perianth-bearing Piperales. Raphides or druses ...
-
Stem Anatomy and the Evolution of Woodiness in Piperales
International Journal of Plant Sciences, 2015Co-Authors: Santiago Trueba, Stefan Wanke, Sarah T. Wagner, Christoph Neinhuis, Nick P. Rowe, Sandrine IsnardAbstract:Premise of research. Piperales displays a wide diversity of growth forms that appears to be linked with differences in cambial activity and subsequent derived wood production. To date, no overall s...
Marie-stéphanie Samain - One of the best experts on this subject based on the ideXlab platform.
-
Peruvian Window-Leaved Peperomia Taxa Display Unique Crystal Macropatterns in High-Altitude Environments
International Journal of Plant Sciences, 2017Co-Authors: Harry T Horner, Stefan Wanke, Birgit Oelschlägel, Marie-stéphanie SamainAbstract:Premise of research. Window-leaved Peperomia taxa (WPs) occur in the Peruvian Andes from near sea level to high altitudes and display curled leaves that are generally exposed to high irradiance and periodic drought, far different from the typically uncurled humid-forest, often-shaded Peperomia taxa. Even though representatives of the latter taxa, as well as other members of the Piperales, have been observed for the presence (type) and location (macropattern) of leaf crystals in previous studies, this special group of WP taxa has missed scrutiny. It was important to determine whether the WP taxa contained the same types of crystals in the same tissue locations and, if not, what any differences could be that are related to their anatomy, environment, and physiology.Methodology. Living leaves of 35 available accessions from the 42 currently recognized taxa of WPs were chemically fixed, some cleared and/or vibratome sectioned or fractured to observe the internal leaf tissues for the presence of crystals compo...
-
Towards uncovering evolution of lineage-specific calcium oxalate crystal patterns in Piperales
Botany, 2015Co-Authors: Harry T Horner, Marie-stéphanie Samain, Sarah T. Wagner, Stefan WankeAbstract:Piperales is among the largest and most diverse angiosperm orders (>4000 species), occurring broadly in tropical and temperate habitats. Twenty-four of the species from 12 genera, representing all lineages of Piperales, except the holoparasitic Hydnoraceae, display a mixture of leaf calcium oxalate crystal types found in previous studies of the two genera of Piperaceae subfamily Piperoideae (Peperomia Ruiz & Pav. and Piper L.). Crystal macropatterns, a result of varying leaf anatomies and diverse habitats, are investigated in a comparative way by using clearings and recent molecular phylogenetic hypotheses to trace crystal types and macropattern evolution. Ancestral character reconstruction reveals that the most recent common ancestor of Piperales had either crystal sand or druses or both and that prisms, raphides, and styloids are derived from the ancestral crystal type(s). These results are also recovered for both the ancestors of the perianth-less and the perianth-bearing Piperales. Raphides or druses ...
-
Major trends in stem anatomy and growth forms in the perianth-bearing Piperales, with special focus on Aristolochia.
Annals of Botany, 2014Co-Authors: Sarah T. Wagner, Marie-stéphanie Samain, Sandrine Isnard, Christoph Neinhuis, Erika Maass, Nick P. Rowe, Linnea Hesse, Jay Bolin, Stefan WankeAbstract:BACKGROUND AND AIMS: The order Piperales has the highest diversity of growth forms among the earliest angiosperm lineages, including trees, shrubs, climbers and herbs. However, within the perianth-bearing Piperales (Asarum, Saruma, Lactoris, Hydnora, Prosopanche, Thottea and Aristolochia), climbing species only occur in the most species-rich genus Aristolochia. This study traces anatomical and morphological traits among these lineages, to detect trends in growth form evolution and developmental processes. METHODS: Transverse stem sections of different developmental stages of representatives of Asarum, Saruma, Lactoris, Hydnora, Thottea and Aristolochia were compared and anatomical traits were linked to growth form evolution. Biomechanical properties of representative climbers were determined in three-point bending tests and are discussed based on the anatomical observations. Growth form evolution of the perianth-bearing Piperales was reconstructed by ancestral character state reconstruction using Mesquite. KEY RESULTS: While species of Asarum and Saruma are exclusively herbaceous, species of the remaining genera show a higher diversity of growth habit and anatomy. This growth form diversity is accompanied by a more complex stem anatomy and appropriate biomechanical properties. The ancestral growth form of the perianth-bearing Piperales is reconstructed with either a shrub-like or herbaceous character state, while the following three backbone nodes in the reconstruction show a shrub-like character state. Accordingly, the climbing habit most probably evolved in the ancestor of Aristolochia. CONCLUSIONS: Since the ancestor of the perianth-bearing Piperales has been reconstructed with a herb- or shrub-like habit, it is proposed that the climbing habit is a derived growth form, which evolved with the diversification of Aristolochia, and might have been a key feature for its diversification. Observed anatomical synapomorphies, such as the perivascular fibres in Lactoris, Thottea and Aristolochia, support the phylogenetic relationship of several lineages within the perianth-bearing Piperales. In addition, the hypothesis that the vegetative organs of the holoparasitic Hydnoraceae are most probably rhizomes is confirmed.
-
Relative substitution rates of nuclear single copy genes (nSCG) are elevated.
2013Co-Authors: Julia Naumann, Marie-stéphanie Samain, Lena Frenzke, Christoph Neinhuis, Karsten Salomo, Joshua P. Der, Eric K. Wafula, Jay F. Bolin, Erika Maass, Claude W. DepamphilisAbstract:The relative substitution rates are shown for five partitioned datasets representing major Piperales lineages. In general, nSCG contribute significantly to the overall rate of the 19-gene-matrix in the different Piperales lineages. Within Hydnoraceae, rates of nSCG regions are 2–3 fold greater than nuclear ribosomal DNA (nrDNA) or mitochondrial DNA (mtDNA). However, comparing the relative rate of Hydnoraceae with other Piperales, the nSCG regions do not exceed the rate of other photosynthetic member such as Verhuellioideae. The partition of nSCG for Piperales is reduced from 14 to the 8 most complete genes for these lineages. Rates were compared using GRate (http://bioinfweb.info/Software/GRate) for different Piperales lineages using Canellales (Canella) as the reference and all other sampled taxa as outgroups.
-
Phylogenetic origin of Hydnoraceae within photosynthetic Piperales.
2013Co-Authors: Julia Naumann, Marie-stéphanie Samain, Lena Frenzke, Christoph Neinhuis, Karsten Salomo, Joshua P. Der, Eric K. Wafula, Jay F. Bolin, Erika Maass, Claude W. DepamphilisAbstract:To compare the performance of individual marker combinations, separate analyses were run and are summarized here. The plastid rbcL and atpB genes are not available for Hydnoraceae. The phylogenetic trees are displayed at the ordinal level, but zoomed in to family level within Piperales (blue). Hydnoraceae are highlighted in red. Both Maximum Likelihood and Bayesian Inference were applied. Nodes with less than 0.85 posterior probability (PP) were collapsed, while nodes with less than 50% bootstrap support (BS) are indicated with a dash. Support values are plotted above branches (PP first, BS second). The obtained topologies are congruent at these levels, but vary in resolution within Piperales. The concatenated dataset that contains all markers (Figure 2D) provides both the best resolution and best support values. In this tree, all Piperales families are statistically supported as monophyletic (considering PP values). Nuclear ribosomal and mitochondrial markers have been calculated separately as well, but those phylogenetic hypotheses are poorly resolved (Figure S1E–F).
Reinhard Zetter - One of the best experts on this subject based on the ideXlab platform.
-
tiny pollen grains first evidence of saururaceae from the late cretaceous of western north america
PeerJ, 2017Co-Authors: Friðgeir Grimsson, Guido W Grimm, Reinhard ZetterAbstract:BACKGROUND: The Saururaceae, a very small family of Piperales comprising only six species in four genera, have a relatively scanty fossil record outside of Europe. The phylogenetic relationships of the four genera to each other are resolved, with the type genus Saururus occurring in both eastern North America and East Asia. No extant species occurs in western Eurasia. The most exceptional find so far has been an inflorescence with in-situ pollen, Saururus tuckerae S.Y.Sm. & Stockey from Eocene of North America with strong affinities to extant species of Saururus. Recent dated trees suggest, however, an Eocene or younger crown age for the family. METHODS: Dispersed fossil pollen grains from the Campanian (82-81 Ma) of North America are compared to dispersed pollen grains from the Eocene strata containing S. tuckerae, the Miocene of Europe, and extant members of the family using combined LM and SEM imaging. RESULTS: The unambiguous fossil record of the Saururaceae is pushed back into the Campanian (82-81 Ma). Comparison with re-investigated pollen from the Eocene of North America, the Miocene of Europe, and modern species of the family shows that pollen morphology in Saururaceae is highly conservative, and remained largely unchanged for the last 80 million years. DISCUSSION: Campanian pollen of Saururaceae precludes young (Eocene or younger) estimates for the Saururaceae root and crown age, but is in-line with maximum age scenarios. Saururus-type pollen appear to represent the primitive pollen morphology of the family. Often overlooked because of its small size, dispersed Saururaceae pollen may provide a unique opportunity to map the geographic history of a small but old group of Piperales, and should be searched for in Paleogene and Cretaceous sediment samples.
Zetter, Reinhard Of Palaeontology, Faculty Of Earth Sciences, Geography And Astronomy, University Of Vienna) - One of the best experts on this subject based on the ideXlab platform.
-
Tiny pollen grains: first evidence of Saururaceae from the Late Cretaceous of western North America
'PeerJ', 2017Co-Authors: Grímsson, Friðgeir Of Palaeontology, Faculty Of Earth Sciences, Geography And Astronomy, University Vienna), Grimm, Guido Of Palaeontology, Faculty Of Earth Sciences, Geography And Astronomy, University Of W. Vienna), Zetter, Reinhard Of Palaeontology, Faculty Of Earth Sciences, Geography And Astronomy, University Of Vienna)Abstract:Background: The Saururaceae, a very small family of Piperales comprising only six species in four genera, have a relatively scanty fossil record outside of Europe. The phylogenetic relationships of the four genera to each other are resolved, with the type genus Saururus occurring in both eastern North America and East Asia. No extant species occurs in western Eurasia. The most exceptional find so far has been an inflorescence with in-situ pollen, Saururus tuckerae S.Y.Sm. & Stockey from Eocene of North America with strong affinities to extant species of Saururus. Recent dated trees suggest, however, an Eocene or younger crown age for the family. Methods: Dispersed fossil pollen grains from the Campanian (82–81 Ma) of North America are compared to dispersed pollen grains from the Eocene strata containing S. tuckerae, the Miocene of Europe, and extant members of the family using combined LM and SEM imaging. Results: The unambiguous fossil record of the Saururaceae is pushed back into the Campanian (82–81 Ma). Comparison with re-investigated pollen from the Eocene of North America, the Miocene of Europe, and modern species of the family shows that pollen morphology in Saururaceae is highly conservative, and remained largely unchanged for the last 80 million years. Discussion: Campanian pollen of Saururaceae precludes young (Eocene or younger) estimates for the Saururaceae root and crown age, but is in-line with maximum age scenarios. Saururus-type pollen appear to represent the primitive pollen morphology of the family. Often overlooked because of its small size, dispersed Saururaceae pollen may provide a unique opportunity to map the geographic history of a small but old group of Piperales, and should be searched for in Paleogene and Cretaceous sediment samples.© 2017 Grímsson et al