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1.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36674711

RESUMO

Abscisic acid (ABA), long known as a plant stress hormone, is present and functionally active in organisms other than those pertaining to the land plant kingdom, including cyanobacteria, fungi, algae, protozoan parasites, lower Metazoa, and mammals. The ancient, cross-kingdom role of this stress hormone allows ABA and its signaling pathway to control cell responses to environmental stimuli in diverse organisms such as marine sponges, higher plants, and humans. Recent advances in our knowledge about the physiological role of ABA and of its mammalian receptors in the control of energy metabolism and mitochondrial function in myocytes, adipocytes, and neuronal cells allow us to foresee therapeutic applications for ABA in the fields of pre-diabetes, diabetes, and cardio- and neuro-protection. Vegetal extracts titrated in their ABA content have shown both efficacy and tolerability in preliminary clinical studies. As the prevalence of glucose intolerance, diabetes, and cardiovascular and neurodegenerative diseases is steadily increasing in both industrialized and rapidly developing countries, new and cost-efficient therapeutics to combat these ailments are much needed to ensure disease-free aging for the current and future working generations.


Assuntos
Diabetes Mellitus , Embriófitas , Animais , Humanos , Ácido Abscísico/metabolismo , Miócitos Cardíacos/metabolismo , Neuroproteção , Diabetes Mellitus/tratamento farmacológico , Reguladores de Crescimento de Plantas/fisiologia , Embriófitas/metabolismo , Hormônios , Mamíferos/metabolismo
2.
Mol Plant ; 16(1): 245-259, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36476805

RESUMO

Salicylic acid (SA) plays a pivotal role in plant response to biotic and abiotic stress. Several core SA signaling regulators and key proteins in SA biosynthesis have been well characterized. However, much remains unknown about the origin, evolution, and early diversification of core elements in plant SA signaling and biosynthesis. In this study, we identified 10 core protein families in SA signaling and biosynthesis across green plant lineages. We found that the key SA signaling receptors, the nonexpresser of pathogenesis-related (NPR) proteins, originated in the most recent common ancestor (MRCA) of land plants and formed divergent groups in the ancestor of seed plants. However, key transcription factors for SA signaling, TGACG motif-binding proteins (TGAs), originated in the MRCA of streptophytes, arguing for the stepwise evolution of core SA signaling in plants. Different from the assembly of the core SA signaling pathway in the ancestor of seed plants, SA exists extensively in green plants, including chlorophytes and streptophyte algae. However, the full isochorismate synthase (ICS)-based SA synthesis pathway was first assembled in the MRCA of land plants. We further revealed that the ancient abnormal inflorescence meristem 1 (AIM1)-based ß-oxidation pathway is crucial for the biosynthesis of SA in chlorophyte algae, and this biosynthesis pathway may have facilitated the adaptation of early-diverging green algae to the high-light-intensity environment on land. Taken together, our findings provide significant insights into the early evolution and diversification of plant SA signaling and biosynthesis pathways, highlighting a crucial role of SA in stress tolerance during plant terrestrialization.


Assuntos
Proteínas de Arabidopsis , Embriófitas , Ácido Salicílico/metabolismo , Plantas/genética , Plantas/metabolismo , Transdução de Sinais , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Embriófitas/metabolismo
3.
Mol Plant ; 16(1): 206-231, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36564945

RESUMO

All plant cells are surrounded by a cell wall that provides cohesion, protection, and a means of directional growth to plants. Cellulose microfibrils contribute the main biomechanical scaffold for most of these walls. The biosynthesis of cellulose, which typically is the most prominent constituent of the cell wall and therefore Earth's most abundant biopolymer, is finely attuned to developmental and environmental cues. Our understanding of the machinery that catalyzes and regulates cellulose biosynthesis has substantially improved due to recent technological advances in, for example, structural biology and microscopy. Here, we provide a comprehensive overview of the structure, function, and regulation of the cellulose synthesis machinery and its regulatory interactors. We aim to highlight important knowledge gaps in the field, and outline emerging approaches that promise a means to close those gaps.


Assuntos
Embriófitas , Celulose , Plantas , Parede Celular , Glucosiltransferases
4.
Nat Plants ; 8(12): 1352-1369, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36550365

RESUMO

The origin of a land flora fundamentally shifted the course of evolution of life on earth, facilitating terrestrialization of other eukaryotic lineages and altering the planet's geology, from changing atmospheric and hydrological cycles to transforming continental erosion processes. Despite algal lineages inhabiting the terrestrial environment for a considerable preceding period, they failed to evolve complex multicellularity necessary to conquer the land. About 470 million years ago, one lineage of charophycean alga evolved complex multicellularity via developmental innovations in both haploid and diploid generations and became land plants (embryophytes), which rapidly diversified to dominate most terrestrial habitats. Genome sequences have provided unprecedented insights into the genetic and genomic bases for embryophyte origins, with some embryophyte-specific genes being associated with the evolution of key developmental or physiological attributes, such as meristems, rhizoids and the ability to form mycorrhizal associations. However, based on the fossil record, the evolution of the defining feature of embryophytes, the embryo, and consequently the sporangium that provided a reproductive advantage, may have been most critical in their rise to dominance. The long timeframe and singularity of a land flora were perhaps due to the stepwise assembly of a large constellation of genetic innovations required to conquer the terrestrial environment.


Assuntos
Evolução Biológica , Embriófitas , Filogenia , Plantas/genética , Embriófitas/genética
5.
Planta ; 256(6): 108, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348172

RESUMO

MAIN CONCLUSION: This review describes zinc sensing and transcriptional regulation of the zinc deficiency response in Arabidopsis, and discusses how their evolutionary conservation in land plants facilitates translational approaches for improving the Zn nutritional value of crop species. Zinc is an essential micronutrient for all living organisms due to its presence in a large number of proteins, as a structural or catalytic cofactor. In plants, zinc homeostasis mechanisms comprise uptake from soil, transport and distribution throughout the plant to provide adequate cellular zinc availability. Here, I discuss the transcriptional regulation of the response to zinc deficiency and the zinc sensing mechanisms in Arabidopsis, and their evolutionary conservation in land plants. The Arabidopsis F-group basic region leucine-zipper (F-bZIP) transcription factors bZIP19 and bZIP23 function simultaneously as sensors of intracellular zinc status, by direct binding of zinc ions, and as the central regulators of the zinc deficiency response, with their target genes including zinc transporters from the ZRT/IRT-like Protein (ZIP) family and nicotianamine synthase enzymes that produce the zinc ligand nicotianamine. I note that this relatively simple mechanism of zinc sensing and regulation, together with the evolutionary conservation of F-bZIP transcription factors across land plants, offer important research opportunities. One of them is to use the F-bZIP-regulated zinc deficiency response as a tractable module for evolutionary and comparative functional studies. Another research opportunity is translational research in crop plants, modulating F-bZIP activity as a molecular switch to enhance zinc accumulation. This should become a useful plant-based solution to alleviate effects of zinc deficiency in soils, which impact crop production and crop zinc content, with consequences for human nutrition globally.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Embriófitas , Humanos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Embriófitas/metabolismo , Zinco/metabolismo , Plantas/metabolismo
6.
Curr Biol ; 32(20): R1028-R1029, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36283350

RESUMO

The Zygnematophyceae is the sister clade to the land plants, but their biology remains mysterious. In a new study, a resolved phylogeny and a scenario for the evolution of multicellularity in that clade are proposed.


Assuntos
Embriófitas , Filogenia , Plantas/genética , Evolução Molecular , Evolução Biológica
7.
Ann Bot ; 130(5): 613-636, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36070407

RESUMO

BACKGROUND: Land plants commonly produce red pigmentation as a response to environmental stressors, both abiotic and biotic. The type of pigment produced varies among different land plant lineages. In the majority of species they are flavonoids, a large branch of the phenylpropanoid pathway. Flavonoids that can confer red colours include 3-hydroxyanthocyanins, 3-deoxyanthocyanins, sphagnorubins and auronidins, which are the predominant red pigments in flowering plants, ferns, mosses and liverworts, respectively. However, some flowering plants have lost the capacity for anthocyanin biosynthesis and produce nitrogen-containing betalain pigments instead. Some terrestrial algal species also produce red pigmentation as an abiotic stress response, and these include both carotenoid and phenolic pigments. SCOPE: In this review, we examine: which environmental triggers induce red pigmentation in non-reproductive tissues; theories on the functions of stress-induced pigmentation; the evolution of the biosynthetic pathways; and structure-function aspects of different pigment types. We also compare data on stress-induced pigmentation in land plants with those for terrestrial algae, and discuss possible explanations for the lack of red pigmentation in the hornwort lineage of land plants. CONCLUSIONS: The evidence suggests that pigment biosynthetic pathways have evolved numerous times in land plants to provide compounds that have red colour to screen damaging photosynthetically active radiation but that also have secondary functions that provide specific benefits to the particular land plant lineage.


Assuntos
Antocianinas , Embriófitas , Antocianinas/metabolismo , Pigmentação , Betalaínas/metabolismo , Plantas/metabolismo , Flavonoides/metabolismo
8.
Curr Biol ; 32(20): 4473-4482.e7, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36055238

RESUMO

The evolution of streptophytes had a profound impact on life on Earth. They brought forth those photosynthetic eukaryotes that today dominate the macroscopic flora: the land plants (Embryophyta).1 There is convincing evidence that the unicellular/filamentous Zygnematophyceae-and not the morphologically more elaborate Coleochaetophyceae or Charophyceae-are the closest algal relatives of land plants.2-6 Despite the species richness (>4,000), wide distribution, and key evolutionary position of the zygnematophytes, their internal phylogeny remains largely unresolved.7,8 There are also putative zygnematophytes with interesting body plan modifications (e.g., filamentous growth) whose phylogenetic affiliations remain unknown. Here, we studied a filamentous green alga (strain MZCH580) from an Austrian peat bog with central or parietal chloroplasts that lack discernible pyrenoids. It represents Mougeotiopsis calospora PALLA, an enigmatic alga that was described more than 120 years ago9 but never subjected to molecular analyses. We generated transcriptomic data of M. calospora strain MZCH580 and conducted comprehensive phylogenomic analyses (326 nuclear loci) for 46 taxonomically diverse zygnematophytes. Strain MZCH580 falls in a deep-branching zygnematophycean clade together with some unicellular species and thus represents a formerly unknown zygnematophycean lineage with filamentous growth. Our well-supported phylogenomic tree lets us propose a new five-order system for the Zygnematophyceae and provides evidence for at least five independent origins of true filamentous growth in the closest algal relatives of land plants. This phylogeny provides a robust and comprehensive framework for performing comparative analyses and inferring the evolution of cellular traits and body plans in the closest relatives of land plants.


Assuntos
Carofíceas , Embriófitas , Estreptófitas , Filogenia , Evolução Biológica , Embriófitas/genética , Carofíceas/genética , Plantas , Solo
9.
Trends Plant Sci ; 27(12): 1203-1205, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36085101

RESUMO

Horizontal gene transfer (HGT) is the transfer of genetic material between organisms. It has been known for some time that HGT in eukaryotes is not a rare phenomenon. A recent study by Ma et al. has shown that HGT has played a crucial role in shaping the evolution of land plants.


Assuntos
Embriófitas , Transferência Genética Horizontal , Transferência Genética Horizontal/genética , Evolução Molecular , Embriófitas/genética , Filogenia
10.
Nat Ecol Evol ; 6(11): 1634-1643, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36175544

RESUMO

The origin of plants and their colonization of land fundamentally transformed the terrestrial environment. Here we elucidate the basis of this formative episode in Earth history through patterns of lineage, gene and genome evolution. We use new fossil calibrations, a relative clade age calibration (informed by horizontal gene transfer) and new phylogenomic methods for mapping gene family origins. Distinct rooting strategies resolve tracheophytes (vascular plants) and bryophytes (non-vascular plants) as monophyletic sister groups that diverged during the Cambrian, 515-494 million years ago. The embryophyte stem is characterized by a burst of gene innovation, while bryophytes subsequently experienced an equally dramatic episode of reductive genome evolution in which they lost genes associated with the elaboration of vasculature and the stomatal complex. Overall, our analyses reveal that extant tracheophytes and bryophytes are both highly derived from a more complex ancestral land plant. Understanding the origin of land plants requires tracing character evolution across a diversity of modern lineages.


Assuntos
Embriófitas , Traqueófitas , Evolução Biológica , Embriófitas/genética , Filogenia , Plantas/genética , Fósseis
11.
Plant Physiol ; 190(4): 2539-2556, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36156105

RESUMO

A signaling complex comprising members of the LORELEI (LRE)-LIKE GPI-anchored protein (LLG) and Catharanthus roseus RECEPTOR-LIKE KINASE 1-LIKE (CrRLK1L) families perceive RAPID ALKALINIZATION FACTOR (RALF) peptides and regulate growth, reproduction, immunity, and stress responses in Arabidopsis (Arabidopsis thaliana). Genes encoding these proteins are members of multigene families in most angiosperms and could generate thousands of signaling complex variants. However, the links between expansion of these gene families and the functional diversification of this critical signaling complex as well as the evolutionary factors underlying the maintenance of gene duplicates remain unknown. Here, we investigated LLG gene family evolution by sampling land plant genomes and explored the function and expression of angiosperm LLGs. We found that LLG diversity within major land plant lineages is primarily due to lineage-specific duplication events, and that these duplications occurred both early in the history of these lineages and more recently. Our complementation and expression analyses showed that expression divergence (i.e. regulatory subfunctionalization), rather than functional divergence, explains the retention of LLG paralogs. Interestingly, all but one monocot and all eudicot species examined had an LLG copy with preferential expression in male reproductive tissues, while the other duplicate copies showed highest levels of expression in female or vegetative tissues. The single LLG copy in Amborella trichopoda is expressed vastly higher in male compared to in female reproductive or vegetative tissues. We propose that expression divergence plays an important role in retention of LLG duplicates in angiosperms.


Assuntos
Arabidopsis , Embriófitas , Magnoliopsida , Arabidopsis/metabolismo , Família Multigênica , Fosfotransferases/genética , Sementes/metabolismo , Embriófitas/genética , Magnoliopsida/genética , Magnoliopsida/metabolismo , Proteínas/genética , Duplicação Gênica , Evolução Molecular , Filogenia
12.
Ann Bot ; 130(4): 457-475, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-35913486

RESUMO

BACKGROUND: In this review, we summarize data concerning action potentials (APs) - long-distance electrical signals in Characean algae and liverworts. These lineages are key in understanding the mechanisms of plant terrestrialization. Liverworts are postulated to be pioneer land plants, whereas aquatic charophytes are considered the closest relatives to land plants. The drastic change of the habitat was coupled with the adaptation of signalling systems to the new environment. SCOPE: APs fulfil the 'all-or-nothing' law, exhibit refractory periods and propagate with a uniform velocity. Their ion mechanism in the algae and liverworts consists of a Ca2+ influx (from external and internal stores) followed by/coincident with a Cl- efflux, which both evoke the membrane potential depolarization, and a K+ efflux leading to repolarization. The molecular identity of ion channels responsible for these fluxes remains unknown. Publication of the Chara braunii and Marchantia polymorpha genomes opened up new possibilities for studying the molecular basis of APs. Here we present the list of genes which can participate in AP electrogenesis. We also point out the differences between these plant species, e.g. the absence of Ca2+-permeable glutamate receptors (GLRs) and Cl--permeable SLAC1 channel homologues in the Chara genome. Both these channels play a vital role in long-distance signalling in liverworts and vascular plants. Among the common properties of APs in liverworts and higher plants is their duration (dozens of seconds) and the speed of propagation (mm s-1), which are much slower than in the algae (seconds, and dozens of mm s-1, respectively). CONCLUSIONS: Future studies with combined application of electrophysiological and molecular techniques should unravel the ion channel proteins responsible for AP generation, their regulation and transduction of those signals to physiological responses. This should also help to understand the adaptation of the signalling systems to the land environment and further evolution of APs in vascular plants.


Assuntos
Embriófitas , Marchantia , Potenciais de Ação , Cálcio/metabolismo , Canais Iônicos/metabolismo , Plantas/genética , Plantas/metabolismo
13.
Plant Cell ; 34(10): 3512-3542, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-35976122

RESUMO

The liverwort Marchantia polymorpha has been utilized as a model for biological studies since the 18th century. In the past few decades, there has been a Renaissance in its utilization in genomic and genetic approaches to investigating physiological, developmental, and evolutionary aspects of land plant biology. The reasons for its adoption are similar to those of other genetic models, e.g. simple cultivation, ready access via its worldwide distribution, ease of crossing, facile genetics, and more recently, efficient transformation, genome editing, and genomic resources. The haploid gametophyte dominant life cycle of M. polymorpha is conducive to forward genetic approaches. The lack of ancient whole-genome duplications within liverworts facilitates reverse genetic approaches, and possibly related to this genomic stability, liverworts possess sex chromosomes that evolved in the ancestral liverwort. As a representative of one of the three bryophyte lineages, its phylogenetic position allows comparative approaches to provide insights into ancestral land plants. Given the karyotype and genome stability within liverworts, the resources developed for M. polymorpha have facilitated the development of related species as models for biological processes lacking in M. polymorpha.


Assuntos
Embriófitas , Marchantia , Evolução Biológica , Células Germinativas Vegetais , Marchantia/genética , Filogenia
14.
Plant Physiol ; 190(1): 85-99, 2022 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-35904762

RESUMO

The evolution of transporting tissues was an important innovation in terrestrial plants that allowed them to adapt to almost all nonaquatic environments. These tissues consist of water-conducting cells and food-conducting cells and bridge plant-soil and plant-air interfaces over long distances. The largest group of land plants, representing about 95% of all known plant species, is associated with morphologically complex transporting tissue in plants with a range of additional traits. Therefore, this entire clade was named tracheophytes, or vascular plants. However, some nonvascular plants possess conductive tissues that closely resemble vascular tissue in their organization, structure, and function. Recent molecular studies also point to a highly conserved toolbox of molecular regulators for transporting tissues. Here, we reflect on the distinguishing features of conductive and vascular tissues and their evolutionary history. Rather than sudden emergence of complex, vascular tissues, plant transporting tissues likely evolved gradually, building on pre-existing developmental mechanisms and genetic components. Improved knowledge of the intimate structure and developmental regulation of transporting tissues across the entire taxonomic breadth of extant plant lineages, combined with more comprehensive documentation of the fossil record of transporting tissues, is required for a full understanding of the evolutionary trajectory of transporting tissues.


Assuntos
Embriófitas , Evolução Biológica , Embriófitas/genética , Evolução Molecular , Fósseis , Filogenia , Plantas/genética
15.
Biomolecules ; 12(7)2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35883518

RESUMO

Flavonoids as a class of important secondary metabolites are widely present in land plants, and chalcone isomerase (CHI) is the key rate-limiting enzyme that participates in catalyzing the stereospecific isomerization of chalcones to yield their corresponding flavanones. However, the phylogenetic dynamics and functional divergence of CHI family genes during the evolutionary path of green plants remains poorly understood. Here, a total of 122 CHI genes were identified by performing a genome-wide survey of 15 representative green plants from the most ancestral basal plant chlorophyte algae to higher angiosperm plants. Phylogenetic, orthologous groups (OG) classification, and genome structure analysis showed that the CHI family genes have evolved into four distinct types (types I-IV) containing eight OGs after gene duplication, and further studies indicated type III CHIs consist of three subfamilies (FAP1, FAP2, and FAP3). The phylogeny showed FAP3 CHIs as an ancestral out-group positioned on the outer layers of the main branch, followed by type IV CHIs, which are placed in an evolutionary intermediate between FAP3 CHIs and bona fide CHIs (including type I and type II). The results imply a potential intrinsic evolutionary connection between CHIs existing in the green plants. The amino acid substitutions occurring in several residues have potentially affected the functional divergence between CHI proteins. This is supported by the analysis of transcriptional divergence and cis-acting element analysis. Evolutionary dynamics analyses revealed that the differences in the total number of CHI family genes in each plant are primarily attributed to the lineage-specific expansion by natural selective forces. The current studies provide a deeper understanding of the phylogenetic relationships and functional diversification of CHI family genes in green plants, which will guide further investigation on molecular characteristics and biological functions of CHIs.


Assuntos
Embriófitas , Liases Intramoleculares , Evolução Molecular , Liases Intramoleculares/genética , Liases Intramoleculares/metabolismo , Filogenia , Proteínas de Plantas/metabolismo , Plantas/metabolismo
16.
Genes (Basel) ; 13(7)2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35885919

RESUMO

Mitochondria are semi-autonomous organelles that produce much of the energy required for cellular metabolism. As descendants of a bacterial symbiont, most mitochondria harbor their own genetic system (mtDNA/mitogenome), with intrinsic machineries for transcription and protein translation. A notable feature of plant mitochondria involves the presence of introns (mostly group II-type) that reside in many organellar genes. The splicing of the mtRNAs relies on the activities of various protein cofactors, which may also link organellar functions with cellular or environmental signals. The splicing of canonical group II introns is aided by an ancient class of RT-like enzymes (IEPs/maturases, MATs) that are encoded by the introns themselves and act specifically on their host introns. The plant organellar introns are degenerated in structure and are generally also missing their cognate intron-encoded proteins. The factors required for plant mtRNA processing are mostly nuclearly-encoded, with the exception of a few degenerated MATs. These are in particular pivotal for the maturation of NADH-dehydrogenase transcripts. In the following review we provide an update on the non-canonical MAT factors in angiosperm mitochondria and summarize the current knowledge of their essential roles in regulating Nad1 expression and complex I (CI) biogenesis during embryogenesis and early plant life.


Assuntos
Embriófitas , DNA Polimerase Dirigida por RNA , Embriófitas/genética , Íntrons/genética , Mitocôndrias/metabolismo , Proteínas/genética , Splicing de RNA/genética , DNA Polimerase Dirigida por RNA/metabolismo
17.
Sci Rep ; 12(1): 12328, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35853967

RESUMO

Zinc finger (Zf)-BED proteins are a novel superfamily of transcription factors that controls numerous activities in plants including growth, development, and cellular responses to biotic and abiotic stresses. Despite their important roles in gene regulation, little is known about the specific functions of Zf-BEDs in land plants. The current study identified a total of 750 Zf-BED-encoding genes in 35 land plant species including mosses, bryophytes, lycophytes, gymnosperms, and angiosperms. The gene family size was somewhat proportional to genome size. All identified genes were categorized into 22 classes based on their specific domain architectures. Of these, class I (Zf-BED_DUF-domain_Dimer_Tnp_hAT) was the most common in the majority of the land plants. However, some classes were family-specific, while the others were species-specific, demonstrating diversity at different classification levels. In addition, several novel functional domains were also predicated including WRKY and nucleotide-binding site (NBS). Comparative genomics, transcriptomics, and proteomics provided insights into the evolutionary history, duplication, divergence, gene gain and loss, species relationship, expression profiling, and structural diversity of Zf-BEDs in land plants. The comprehensive study of Zf-BEDs in Gossypium sp., (cotton) also demonstrated a clear footprint of polyploidization. Overall, this comprehensive evolutionary study of Zf-BEDs in land plants highlighted significant diversity among plant species.


Assuntos
Embriófitas , Proteínas de Plantas , Embriófitas/genética , Embriófitas/metabolismo , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Família Multigênica , Filogenia , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Fatores de Transcrição/metabolismo , Dedos de Zinco/genética
18.
Nat Plants ; 8(7): 735-740, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35854003

RESUMO

In angiosperms, a negative feedback pathway involving CLAVATA3 (CLV3) peptide and WUSCHEL transcription factor maintains the stem-cell population in the shoot apical meristem and is central for continued shoot growth and organogenesis. An intriguing question is how this cell-signalling system was established during the evolution of land plants. On the basis of two recent studies on CLV3/ESR-related (CLE) genes, this paper proposes a model for the evolution of meristem zonation. The model suggests that a stem-cell-limiting CLV3 pathway is derived from stem-cell-promoting CLE pathways conserved in land pants by gene duplication in the angiosperm lineage. The model can be examined in the future by genomic and developmental studies on diverse plant species.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Embriófitas , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Embriófitas/metabolismo , Duplicação Gênica , Regulação da Expressão Gênica de Plantas , Meristema/metabolismo
19.
RNA Biol ; 19(1): 897-907, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35811474

RESUMO

RNA splicing refers to a process by which introns of a pre-mRNA are excised and the exons at both ends are joined together. Chloroplast introns are inherently self-splicing ribozymes, but over time, they have lost self-splicing ability due to the degeneration of intronic elements. Thus, the splicing of chloroplast introns relies heavily on nuclear-encoded splicing factors, which belong to diverse protein families. Different splicing factors and their shared intron targets are supposed to form ribonucleoprotein particles (RNPs) to facilitate intron splicing. As characterized in a previous review, around 14 chloroplast intron splicing factors were identified until 2010. However, only a few genetic and biochemical evidence has shown that these splicing factors are required for the splicing of one or several introns. The roles of splicing factors are generally believed to facilitate intron folding; however, the precise role of each protein in RNA splicing remains ambiguous. This may be because the precise binding site of most of these splicing factors remains unexplored. In the last decade, several new splicing factors have been identified. Also, several splicing factors were found to bind to specific sequences within introns, which enhanced the understanding of splicing factors. Here, we summarize recent progress on the splicing factors in land plant chloroplasts and discuss their possible roles in chloroplast RNA splicing based on previous studies.


Assuntos
Embriófitas , Splicing de RNA , Cloroplastos/genética , Cloroplastos/metabolismo , Embriófitas/genética , Embriófitas/metabolismo , Íntrons , Fatores de Processamento de RNA/genética , RNA de Plantas/metabolismo
20.
Cladistics ; 38(6): 649-662, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35779275

RESUMO

Marchantiopsida (complex thalloid liverworts) are one of the earliest lineages of embryophytes (land plants), and well-known for their air pores and chambers, pegged rhizoids, and absence of organellular RNA editing sites. Despite their importance to an understanding of early embryophyte evolution, many key nodes within this class remain poorly resolved, owing to the paucity of genetic loci previously available for phylogenetic analyses. Here, we sequenced 54 plastomes, representing 28 genera, nearly all families, and all orders of Marchantiopsida. Based on these plastomes, we present a hypothesis of deep relationships within the class, and make the first investigations of gene contents and synteny. Overall, the Marchantiopsida plastomes were well-conserved, with the exception of the genus Cyathodium that has plastomes with higher GC content, fewer single sequence repeats (SSRs), and more structural variations, implying that this genus might possess RNA editing sites. Abundant repetitive elements and six highly divergent regions were identified as suitable for future infrafamilial taxonomic studies. The phylogenetic topology of Sphaerocarpales, Neohodgsoniales and Blasiales within Marchantiopsida was essentially congruent with previous studies but generally we obtained higher support values. Based on molecular evidence and previous morphological studies, we include Lunulariales in Marchantiales and suggest the retention of narrowed delimitation of monotypic families. The phylogenetic relationships within Marchantiales were better resolved, and 13 monophyletic families were recovered. Our analyses confirmed that the loss of intron 2 of ycf3 is a synapomorphy of Marchantiidae. Finally, we propose a new genus, Asterellopsis (Aytoniaceae), and present an updated classification of Marchantiopsida. The highly supported phylogenetic backbone provided here establishes a framework for future comparative and evolutionary studies of the complex thalloid liverworts.


Assuntos
Embriófitas , Genoma de Cloroplastos , Hepatófitas , Humanos , Filogenia , Genoma de Cloroplastos/genética , Hepatófitas/genética , Sintenia , Embriófitas/genética
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