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Plant Cell Reports Jul 2023Novel episomal systems have the potential to accelerate plastid genetic engineering for application in plant synthetic biology. Plastids represent valuable subcellular... (Review)
Review
Novel episomal systems have the potential to accelerate plastid genetic engineering for application in plant synthetic biology. Plastids represent valuable subcellular compartments for genetic engineering of plants with intrinsic advantages to engineering the nucleus. The ability to perform site-specific transgene integration by homologous recombination (HR), coordination of transgene expression in operons, and high production of heterologous proteins, all make plastids an attractive target for synthetic biology. Typically, plastid engineering is performed by homologous recombination; however, episomal-replicating vectors have the potential to accelerate the design/build/test cycles for plastid engineering. By accelerating the timeline from design to validation, it will be possible to generate translational breakthroughs in fields ranging from agriculture to biopharmaceuticals. Episomal-based plastid engineering will allow precise single step metabolic engineering in plants enabling the installation of complex synthetic circuits with the ambitious goal of reaching similar efficiency and flexibility of to the state-of-the-art genetic engineering of prokaryotic systems. The prospect to design novel episomal systems for production of transplastomic marker-free plants will also improve biosafety for eventual release in agriculture.
Topics: Genetic Engineering; Plastids; Plants; Transgenes; Metabolic Engineering; DNA; Plants, Genetically Modified; Transformation, Genetic
PubMed: 37127835
DOI: 10.1007/s00299-023-03020-x -
Current Biology : CB Apr 2018de Vries and Archibald introduce the topic of plastid genomes - prokaryotic genomes housed within eukaryotic algae and plants. (Review)
Review
de Vries and Archibald introduce the topic of plastid genomes - prokaryotic genomes housed within eukaryotic algae and plants.
Topics: Cyanobacteria; Evolution, Molecular; Genome, Plastid; Phylogeny; Plants; Plastids; Symbiosis
PubMed: 29689202
DOI: 10.1016/j.cub.2018.01.027 -
Current Opinion in Biotechnology Feb 2018Metabolic pathway engineering by transgene expression from the plastid (chloroplast) genome offers significant attractions, including straightforward multigene... (Review)
Review
Metabolic pathway engineering by transgene expression from the plastid (chloroplast) genome offers significant attractions, including straightforward multigene engineering by pathway expression from operons, high transgene expression levels, and increased transgene containment due to maternal inheritance of plastids in most crops. In addition, it provides direct access to the large and diverse metabolite pools in chloroplasts and non-green plastid types. Here, we review recent progress with extending the toolbox for plastid engineering and highlight selected applications in the area of metabolic engineering, including the combined engineering of nuclear and plastid genomes for the production of artemisinic acid, the direct harness of chloroplast reducing power for the synthesis of dhurrin and the use of an edible host for the production of astaxanthin.
Topics: Antioxidants; Metabolic Engineering; Plants, Genetically Modified; Plastids; Transformation, Genetic; Transgenes
PubMed: 28738208
DOI: 10.1016/j.copbio.2017.07.004 -
Annual Review of Plant Biology 2006Plant cells store genetic information in the genomes of three organelles: the nucleus, plastid, and mitochondrion. The nucleus controls most aspects of organelle gene... (Review)
Review
Plant cells store genetic information in the genomes of three organelles: the nucleus, plastid, and mitochondrion. The nucleus controls most aspects of organelle gene expression, development, and function. In return, organelles send signals to the nucleus to control nuclear gene expression, a process called retrograde signaling. This review summarizes our current understanding of plastid-to-nucleus retrograde signaling, which involves multiple, partially redundant signaling pathways. The best studied is a pathway that is triggered by buildup of Mg-ProtoporphyrinIX, the first intermediate in the chlorophyll branch of the tetrapyrrole biosynthetic pathway. In addition, there is evidence for a plastid gene expression-dependent pathway, as well as a third pathway that is dependent on the redox state of photosynthetic electron transport components. Although genetic studies have identified several players involved in signal generation, very little is known of the signaling components or transcription factors that regulate the expression of hundreds of nuclear genes.
Topics: Cell Nucleus; Chloroplasts; Gene Expression; Oxidation-Reduction; Plastids; Signal Transduction
PubMed: 16669780
DOI: 10.1146/annurev.arplant.57.032905.105310 -
Biochimica Et Biophysica Acta Feb 2010It is now widely accepted that an endosymbiotic cyanobacterium evolved into the plastid of the primary photosynthetic eukaryotes: glaucocystophytes, red algae, and green... (Review)
Review
It is now widely accepted that an endosymbiotic cyanobacterium evolved into the plastid of the primary photosynthetic eukaryotes: glaucocystophytes, red algae, and green plants. It has been thought that during the evolution of plants, the peptidoglycan wall (or murein) was lost from the endosymbiont immediately after the branching off of the glaucocystophytes, which have peptidoglycan-armed plastids termed cyanelles. However, we found that the moss Physcomitrella patens has all of the genes for peptidoglycan biosynthesis with the exception of one racemase. The aim of the present review is to summarize recent findings on plastid peptidoglycan and to present a hypothesis for the evolution of plastids containing peptidoglycan. Gene knockout experiments for the Mur(ein) genes, including MurE in P. patens, showed that the peptidoglycan synthesis pathway is related to plastid division, although no structure can be detected between the inner and outer envelopes of the chloroplasts by electron microscopy. On the other hand, MurE in Arabidopsis thaliana has a function in plastid gene expression and not in division. Based on data regarding plant genomes and antibiotic treatment experiments of plastid division, we propose that the loss of peptidoglycan occurred independently at least three times during plant evolution: from the lineage of red algae, from the chlorophytes, and during land plant evolution.
Topics: Arabidopsis; Bryopsida; Gene Expression Regulation, Plant; Genes, Plant; Peptidoglycan; Plastids
PubMed: 19647785
DOI: 10.1016/j.bbagen.2009.07.020 -
Biochemistry. Biokhimiia Jun 2017This review presents current views on the plastid genomes of higher plants and summarizes data on the size, structural organization, gene content, and other features of... (Review)
Review
This review presents current views on the plastid genomes of higher plants and summarizes data on the size, structural organization, gene content, and other features of plastid DNAs. Special emphasis is placed on the properties of organization of land plant plastid genomes (nucleoids) that distinguish them from bacterial genomes. The prospects of genetic engineering of chloroplast genomes are discussed.
Topics: DNA, Plant; Genetic Engineering; Genome, Plastid; Plastids
PubMed: 28601077
DOI: 10.1134/S0006297917060049 -
Plant & Cell Physiology May 2024Chloroplasts/plastids are unique organelles found in plant cells and some algae and are responsible for performing essential functions such as photosynthesis. The... (Review)
Review
Chloroplasts/plastids are unique organelles found in plant cells and some algae and are responsible for performing essential functions such as photosynthesis. The plastid genome, consisting of circular and linear DNA molecules, is packaged and organized into specialized structures called nucleoids. The composition and dynamics of these nucleoids have been the subject of intense research, as they are critical for proper plastid functions and development. In this mini-review, recent advances in understanding the organization and regulation of plastid nucleoids are overviewed, with a focus on the various proteins and factors that regulate the shape and dynamics of nucleoids, including DNA-binding proteins and membrane anchorage proteins. The dynamic nature of nucleoid organization, which is influenced by a variety of developmental cues and the cell cycle, is also examined.
Topics: Plastids; Chloroplasts; Plant Proteins; Plants
PubMed: 37542434
DOI: 10.1093/pcp/pcad090 -
Biochimica Et Biophysica Acta Sep 2015Sigma factors are the predominant factors involved in transcription regulation in bacteria. These factors can recruit the core RNA polymerase to promoters with specific... (Review)
Review
Sigma factors are the predominant factors involved in transcription regulation in bacteria. These factors can recruit the core RNA polymerase to promoters with specific DNA sequences and initiate gene transcription. The plastids of higher plants originating from an ancestral cyanobacterial endosymbiont also contain sigma factors that are encoded by a small family of nuclear genes. Although all plastid sigma factors contain sequences conserved in bacterial sigma factors, a considerable number of distinct traits have been acquired during evolution. The present review summarises recent advances concerning the regulation of the structure, function and activity of plastid sigma factors since their discovery nearly 40 years ago. We highlight the specialised roles and overlapping redundant functions of plastid sigma factors according to their promoter selectivity. We also focus on the mechanisms that modulate the activity of sigma factors to optimise plastid function in response to developmental cues and environmental signals. This article is part of a Special Issue entitled: Chloroplast Biogenesis.
Topics: Plastids; Promoter Regions, Genetic; Sigma Factor; Transcription, Genetic
PubMed: 25596450
DOI: 10.1016/j.bbabio.2015.01.001 -
Biochimica Et Biophysica Acta. Gene... Mar 2021The extensive processing and protein-assisted stabilization of transcripts have been taken as evidence for a viewpoint that the control of gene expression had shifted... (Review)
Review
The extensive processing and protein-assisted stabilization of transcripts have been taken as evidence for a viewpoint that the control of gene expression had shifted entirely in evolution from transcriptional in the bacterial endosymbiont to posttranscriptional in the plastid. This suggestion is however at odds with many observations on plastid gene transcription. Chloroplasts of flowering plants and mosses contain two or more RNA polymerases with distinct promoter preference and division of labor for the coordinated synthesis of plastid RNAs. Plant and algal plastids further possess multiple nonredundant sigma factors that function as transcription initiation factors. The controlled accumulation of plastid sigma factors and modification of their activity by sigma-binding proteins and phosphorylation constitute additional transcriptional regulatory strategies. Plant and algal plastids also contain dedicated one- or two-component transcriptional regulators. Transcription initiation thus continues to form a critical control point at which varied developmental and environmental signals intersect with plastid gene expression.
Topics: DNA-Directed RNA Polymerases; Gene Expression Regulation, Plant; Plant Proteins; Plastids; Transcription Initiation, Genetic
PubMed: 33561560
DOI: 10.1016/j.bbagrm.2021.194689 -
Plant Cell Reports Jul 2019
Topics: Chloroplasts; Homeostasis; Organelle Biogenesis; Plants; Plastids; Protein Transport; Signal Transduction; Stress, Physiological
PubMed: 31165906
DOI: 10.1007/s00299-019-02437-7