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1.
J Agric Food Chem ; 67(42): 11607-11615, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31560536

RESUMO

ζ-carotene desaturase (ZDS) is a key enzyme in carotenoid biosynthesis and plays an important role in plant photosynthesis. We characterized an albino leaf-color mutant obtained from ethyl methanesulfonate treatment: albino and seedling lethality 1 (ale1). The material contains a chloroplast thylakoid defect where photosynthetic pigments declined and reactive oxygen species accumulated resulting in ale1 death within 3 weeks. Positional cloning and sequencing revealed that there was a single base substitution in ALE1, which encoded a ZDS involved in carotenoid biosynthesis. RNAi and complementation tests confirmed the identity of ALE1. Subcellular localization showed that the ALE1 protein is localized in the chloroplast. Expression analysis indicated that the genes involved in chlorophyll and carotenoid biosynthesis were downregulated. We conclude that ALE1 plays an important role in chloroplast and plant growth in rice.


Assuntos
Cloroplastos/enzimologia , Oryza/crescimento & desenvolvimento , Oxirredutases/genética , Proteínas de Plantas/genética , Clorofila/metabolismo , Cloroplastos/genética , Regulação da Expressão Gênica de Plantas , Oryza/enzimologia , Oryza/genética , Oxirredutases/metabolismo , Fotossíntese , Proteínas de Plantas/metabolismo , Interferência de RNA , Plântula/enzimologia , Plântula/genética , Plântula/crescimento & desenvolvimento
2.
BMC Plant Biol ; 19(1): 350, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409298

RESUMO

BACKGROUND: The pentatricopeptide repeat (PPR) gene family, which contains multiple 35-amino acid repeats, constitutes one of the largest gene families in plants. PPR proteins function in organelles to target specific transcripts and are involved in plant development and growth. However, the function of PPR proteins in cotton is still unknown. RESULTS: In this study, we characterized a PPR gene YELLOW-GREEN LEAF (GhYGL1d) that is required for cotton plastid development. The GhYGL1d gene has a DYW domain in C-terminal and is highly express in leaves, localized to the chloroplast fractions. GhYGL1d share high amino acid-sequence homology with AtECB2. In atecb2 mutant, overexpression of GhYGL1d rescued the seedling lethal phenotype and restored the editing of accD and ndhF transcripts. Silencing of GhYGL1d led to the reduction of chlorophyll and phenotypically yellow-green leaves in cotton. Compared with wild type, GhYGL1d-silenced cotton showed significant deformations of thylakoid structures. Furthermore, the transcription levels of plastid-encoded polymerase (PEP) and nuclear-encoded polymerase (NEP) dependent genes were decreased in GhYGL1d-silenced cotton. CONCLUSIONS: Our data indicate that GhYGL1d not only contributes to the editing of accD and ndhF genes, but also affects the expression of NEP- and PEP-dependent genes to regulate the development of thylakoids, and therefore regulates leaf variegation in cotton.


Assuntos
Cloroplastos/genética , Gossypium/genética , Proteínas de Plantas/fisiologia , Cloroplastos/metabolismo , Cloroplastos/fisiologia , Gossypium/anatomia & histologia , Gossypium/metabolismo , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
3.
Food Chem ; 300: 125205, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31330372

RESUMO

For efficient extraction of amplifiable DNA from edible vegetable oils, we developed a novel DNA extraction approach based on the non-silica-based dipolar nanocomposites. The nanoparticle comprises a hydrophilic polymethyl methacrylate core with abundant capillaries, hydrophilic vesicles decorated with molecules having DNA affinity and a coating hydrophobic polystyrene layer. The nanoparticles are soluble in oil, adsorb the DNA from the aqueous phase and gave a high DNA recovery ratio. All DNA extracts from fully refined vegetable oil soybean, peanut, rapeseed, and cottonseed oils, including their blends, were sufficiently pure to be amplified by real-time PCR targeting the chloroplast ribulose-1,5-bisphosphate gene (rbcL), therefore, the species of origin and their ratios in mixed vegetable oils blended from two or three oil-species could be determined. These results indicate that the novel DNA isolation and real-time PCR kit is a simple, sensitive and efficient tool for the species identification and traceability in refined vegetable oils.


Assuntos
DNA de Plantas/isolamento & purificação , Nanopartículas/química , Óleos Vegetais/química , Reação em Cadeia da Polimerase em Tempo Real/métodos , Verduras/genética , Fracionamento Químico/métodos , Cloroplastos/genética , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Polimetil Metacrilato/química , Ribulosefosfatos/genética , Dióxido de Silício
4.
Nat Plants ; 5(6): 581-588, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31182842

RESUMO

Chloroplasts are integral to sensing biotic and abiotic stress in plants, but their role in transducing Ca2+-mediated stress signals remains poorly understood1,2. Here we identify cMCU, a member of the mitochondrial calcium uniporter (MCU) family, as an ion channel mediating Ca2+ flux into chloroplasts in vivo. Using a toolkit of aequorin reporters targeted to chloroplast stroma and the cytosol in cMCU wild-type and knockout lines, we provide evidence that stress-stimulus-specific Ca2+ dynamics in the chloroplast stroma correlate with expression of the channel. Fast downstream signalling events triggered by osmotic stress, involving activation of the mitogen-activated protein kinases (MAPK) MAPK3 and MAPK6, and the transcription factors MYB60 and ethylene-response factor 6 (ERF6), are influenced by cMCU activity. Relative to wild-type plants, cMCU knockouts display increased resistance to long-term water deficit and improved recovery on rewatering. Modulation of stromal Ca2+ in specific processing of stress signals identifies cMCU as a component of plant environmental sensing.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Canais de Cálcio/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Proteínas de Cloroplastos/metabolismo , Cloroplastos/metabolismo , Proteínas Mitocondriais/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cálcio/metabolismo , Canais de Cálcio/genética , Proteínas de Transporte de Cátions/genética , Proteínas de Cloroplastos/genética , Cloroplastos/genética , Escherichia coli , Técnicas de Inativação de Genes , Sistema de Sinalização das MAP Quinases , Proteínas Mitocondriais/genética , Pressão Osmótica
5.
BMC Plant Biol ; 19(1): 265, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31221088

RESUMO

BACKGROUND: Chloroplast biogenesis, a complex process in higher plants, is the key to photoautotrophic growth in plants. White virescent (wv) mutants have been used to unfold the molecular mechanisms underlying the regulation of chloroplast development and chloroplast gene expression in plants. However, most of genes controlling white virescent phenotype still remain unknown. RESULTS: In this study, we identified a temperature- and light intensity-sensitive mutant, named as wv. The content of chlorophyll was dramatically decreased in the immature leaves of wv mutant under the conditions of low temperature and high-light intensity. TEM observation showed that the chloroplasts in the young leaves of wv mutant lacked an organized thylakoid membrane, whereas crescent-shaped chloroplasts with well-developed stromal and stacked grana thylakoids in the mature leaves were developed. Immunoblot analyses suggested that proteins of photosynthetic complexes were decreased substantially in wv mutants. Based on map-based cloning and transgenic analysis, we determined that the wv phenotype was caused by single base mutation in the first intron of WV gene, which encoded a thioredoxin protein with 365 amino acids. qRT-PCR analysis revealed that the expression of WV gene was significantly down-regulated in wv mutant. In addition, knockdown of WV gene through RNAi also resulted in white virescent young leaves, suggesting that the mutation possibly blocks the differentiation of chloroplasts through inhibiting the expression of WV gene. Furthermore, the expression of WV peaked in apical buds and gradually decreased along with the developmental stage, which was consistent with the wv mutant phenotype. Expression analysis of chloroplast-encoded genes by qRT-PCR showed that the wv mutation affected the expression pattern of chloroplast-encoded PEP dependent genes. CONCLUSION: Our results suggested that wv mutant was sensitive to low temperature and light intensity. WV gene was essential for chloroplast differentiation. A single base mutation in the first intron resulted in down-regulation of WV gene expression, which inhibited the expression of chloroplast-encoded genes, thereby blocking chloroplast formation and chlorophyll synthesis.


Assuntos
Cloroplastos/genética , Lycopersicon esculentum/genética , Tiorredoxinas/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Temperatura Baixa , Genes de Plantas , Luz , Lycopersicon esculentum/crescimento & desenvolvimento , Lycopersicon esculentum/efeitos da radiação , Mutação , Fenótipo , Fotossíntese/genética , Alinhamento de Sequência , Tiorredoxinas/fisiologia
6.
Nat Commun ; 10(1): 2630, 2019 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-31201314

RESUMO

Phytochromes initiate chloroplast biogenesis by activating genes encoding the photosynthetic apparatus, including photosynthesis-associated plastid-encoded genes (PhAPGs). PhAPGs are transcribed by a bacterial-type RNA polymerase (PEP), but how phytochromes in the nucleus activate chloroplast gene expression remains enigmatic. We report here a forward genetic screen in Arabidopsis that identified NUCLEAR CONTROL OF PEP ACTIVITY (NCP) as a necessary component of phytochrome signaling for PhAPG activation. NCP is dual-targeted to plastids and the nucleus. While nuclear NCP mediates the degradation of two repressors of chloroplast biogenesis, PIF1 and PIF3, NCP in plastids promotes the assembly of the PEP complex for PhAPG transcription. NCP and its paralog RCB are non-catalytic thioredoxin-like proteins that diverged in seed plants to adopt nonredundant functions in phytochrome signaling. These results support a model in which phytochromes control PhAPG expression through light-dependent double nuclear and plastidial switches that are linked by evolutionarily conserved and dual-localized regulatory proteins.


Assuntos
Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , Chaperonas Moleculares/metabolismo , Fitocromo/metabolismo , Transcrição Genética/fisiologia , Arabidopsis/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Cloroplastos/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Luz , Fotossíntese/fisiologia , Plantas Geneticamente Modificadas , Plastídeos/genética , Plastídeos/metabolismo , Transdução de Sinais/fisiologia , Transcrição Genética/efeitos da radiação
7.
Nat Commun ; 10(1): 2629, 2019 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-31201355

RESUMO

Light initiates chloroplast biogenesis by activating photosynthesis-associated genes encoded by not only the nuclear but also the plastidial genome, but how photoreceptors control plastidial gene expression remains enigmatic. Here we show that the photoactivation of phytochromes triggers the expression of photosynthesis-associated plastid-encoded genes (PhAPGs) by stimulating the assembly of the bacterial-type plastidial RNA polymerase (PEP) into a 1000-kDa complex. Using forward genetic approaches, we identified REGULATOR OF CHLOROPLAST BIOGENESIS (RCB) as a dual-targeted nuclear/plastidial phytochrome signaling component required for PEP assembly. Surprisingly, RCB controls PhAPG expression primarily from the nucleus by interacting with phytochromes and promoting their localization to photobodies for the degradation of the transcriptional regulators PIF1 and PIF3. RCB-dependent PIF degradation in the nucleus signals the plastids for PEP assembly and PhAPG expression. Thus, our findings reveal the framework of a nucleus-to-plastid anterograde signaling pathway by which phytochrome signaling in the nucleus controls plastidial transcription.


Assuntos
Proteínas de Arabidopsis/metabolismo , Cloroplastos/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Fitocromo/metabolismo , Tiorredoxinas/metabolismo , Transcrição Genética/fisiologia , Arabidopsis/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Núcleo Celular/metabolismo , Cloroplastos/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Luz , Fotossíntese/fisiologia , Plantas Geneticamente Modificadas , Plastídeos/genética , Plastídeos/metabolismo , Proteólise , Transdução de Sinais/fisiologia , Transcrição Genética/efeitos da radiação
8.
J Agric Food Chem ; 67(26): 7249-7257, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31244201

RESUMO

The duration of the rice growth phase has always been an important target trait. The identification of mutations in rice that alter these processes and result in a shorter growth phase could have potential benefits for crop production. In this study, we isolated an early aging rice mutant, pe-1, with light green leaves, using γ-mutated indica rice cultivar and subsequent screening methods, which is known as the phytochrome synthesis factor Se5 that controls rice flowering. The pe-1 plant is accompanied by a decreased chlorophyll content, an enhanced photosynthesis, and a decreased pollen fertility. PE-1, a close homologue of HY1, is localized in the chloroplast. Expression pattern analysis indicated that PE-1 was mainly expressed in roots, stems, leaves, leaf sheaths, and young panicles. The knockout of PE-1 using the CRISPR/Cas9 system decreased the chlorophyll content and downregulated the expression of PE-1-related genes. Furthermore, the chloroplasts of pe-1 were filled with many large-sized starch grains, and the number of osmiophilic granules (a chloroplast lipid reservoir) was significantly decreased. Altogether, our findings suggest that PE-1 functions as a master regulator to mediate in chlorophyll biosynthesis and photosynthetic pathways.


Assuntos
Cloroplastos/metabolismo , Heme Oxigenase-1/metabolismo , Oryza/enzimologia , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Clorofila/metabolismo , Cloroplastos/genética , Regulação da Expressão Gênica de Plantas , Heme Oxigenase-1/genética , Mutação , Oryza/genética , Oryza/metabolismo , Fotossíntese , Proteínas de Plantas/genética
9.
Int J Mol Sci ; 20(9)2019 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-31060231

RESUMO

Three Apiaceae species Ledebouriella seseloides, Peucedanum japonicum, and Glehnia littoralis are used as Asian herbal medicines, with the confusingly similar common name "Bang-poong". We characterized the complete chloroplast (cp) genomes and 45S nuclear ribosomal DNA (45S nrDNA) sequences of two accessions for each species. The complete cp genomes of G. littoralis, L. seseloides, and P. japonicum were 147,467, 147,830, and 164,633 bp, respectively. Compared to the other species, the P. japonicum cp genome had a huge inverted repeat expansion and a segmental inversion. The 45S nrDNA cistron sequences of the three species were almost identical in size and structure. Despite the structural variation in the P. japonicum cp genome, phylogenetic analysis revealed that G. littoralis diverged 5-6 million years ago (Mya), while P. japonicum diverged from L. seseloides only 2-3 Mya. Abundant copy number variations including tandem repeats, insertion/deletions, and single nucleotide polymorphisms, were found at the interspecies level. Intraspecies-level polymorphism was also found for L. seseloides and G. littoralis. We developed nine PCR barcode markers to authenticate all three species. This study characterizes the genomic differences between L. seseloides, P. japonicum, and G. littoralis; provides a method of species identification; and sheds light on the evolutionary history of these three species.


Assuntos
Apiaceae/classificação , Apiaceae/genética , Código de Barras de DNA Taxonômico , Rearranjo Gênico , Genoma de Cloroplastos , Plantas Medicinais/classificação , Plantas Medicinais/genética , Cloroplastos/genética , Variações do Número de Cópias de DNA , Genômica/métodos , Mutação , Fases de Leitura Aberta , Filogenia , RNA Ribossômico/genética , Análise de Sequência de DNA , Sequências de Repetição em Tandem
10.
Nat Plants ; 5(5): 505-511, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31036912

RESUMO

The engineering of plant genomes presents exciting opportunities to modify agronomic traits and to produce high-value products in plants. Expression of foreign proteins from transgenes in the chloroplast genome offers advantages that include the capacity for prodigious protein output, the lack of transgene silencing and the ability to express multicomponent pathways from polycistronic mRNA. However, there remains a need for robust methods to regulate plastid transgene expression. We designed orthogonal activators that boost the expression of chloroplast transgenes harbouring cognate cis-elements. Our system exploits the programmable RNA sequence specificity of pentatricopeptide repeat proteins and their native functions as activators of chloroplast gene expression. When expressed from nuclear transgenes, the engineered proteins stimulate the expression of plastid transgenes by up to ~40-fold, with maximal protein abundance approaching that of Rubisco. This strategy provides a means to regulate and optimize the expression of foreign genes in chloroplasts and to avoid deleterious effects of their products on plant growth.


Assuntos
Proteínas de Arabidopsis/genética , Cloroplastos/genética , Regulação da Expressão Gênica de Plantas/genética , Genes de Troca/genética , Engenharia de Proteínas , Transgenes/genética , Eletroforese em Gel de Poliacrilamida , Immunoblotting , Engenharia de Proteínas/métodos , Proteínas de Ligação a RNA/genética
11.
Plant Cell Rep ; 38(7): 803-818, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31079194

RESUMO

Plant cells are characterized by a unique group of interconvertible organelles called plastids, which are descended from prokaryotic endosymbionts. The most studied plastid type is the chloroplast, which carries out the ancestral plastid function of photosynthesis. During the course of evolution, plastid activities were increasingly integrated with cellular metabolism and functions, and plant developmental processes, and this led to the creation of new types of non-photosynthetic plastids. These include the chromoplast, a carotenoid-rich organelle typically found in flowers and fruits. Here, we provide an introduction to non-photosynthetic plastids, and then review the structures and functions of chromoplasts in detail. The role of chromoplast differentiation in fruit ripening in particular is explored, and the factors that govern plastid development are examined, including hormonal regulation, gene expression, and plastid protein import. In the latter process, nucleus-encoded preproteins must pass through two successive protein translocons in the outer and inner envelope membranes of the plastid; these are known as TOC and TIC (translocon at the outer/inner chloroplast envelope), respectively. The discovery of SP1 (suppressor of ppi1 locus1), which encodes a RING-type ubiquitin E3 ligase localized in the plastid outer envelope membrane, revealed that plastid protein import is regulated through the selective targeting of TOC complexes for degradation by the ubiquitin-proteasome system. This suggests the possibility of engineering plastid protein import in novel crop improvement strategies.


Assuntos
Cloroplastos/metabolismo , Plastídeos/metabolismo , Proteínas de Cloroplastos/genética , Proteínas de Cloroplastos/metabolismo , Cloroplastos/genética , Organelas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plasmídeos/genética , Plastídeos/genética , Transporte Proteico
12.
Plant Cell Rep ; 38(7): 825-833, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31139894

RESUMO

Recently, plants have emerged as a lucrative alternative system for the production of recombinant proteins, as recombinant proteins produced in plants are safer and cheaper than those produced in bacteria and animal cell-based production systems. To obtain high yields in plants, recombinant proteins are produced in chloroplasts using different strategies. The first strategy is based on chloroplast transformation, followed by gene expression and translation in chloroplasts. This has proven to be a powerful approach for the production of proteins at high levels. The second approach is based on nuclear transformation, followed by post-translational import of proteins from the cytosol into chloroplasts. In the nuclear transformation approach, foreign genes are stably integrated into the nuclear genome or transiently expressed in the nucleus by non-integrating T-DNA. Although this approach also has great potential for protein production at high levels, it has not been thoroughly investigated. In this review, we focus on nuclear transformation-based protein expression and its subsequent sequestration in chloroplasts, and summarize the different strategies used for high-level production of recombinant proteins. We also discuss future directions for further improvements in protein production in chloroplasts through nuclear transformation-based gene expression.


Assuntos
Núcleo Celular/metabolismo , Cloroplastos/metabolismo , Cloroplastos/genética , Transporte Proteico/genética , Transporte Proteico/fisiologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transformação Genética/genética
13.
J Genet ; 982019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30945682

RESUMO

Dipentodon is a monotypic genus of Dipentodontaceae and the only species, Dipentodon sinicus, is scattered in southwest China as well as adjacent Myanmar, northeast India and northern Vietnam. This species was evaluated as vulnerable in 'China Species Red List'. Here, we assembled and characterized the complete chloroplast (cp) genome of D. sinicus using Illumina sequencing data for the first time. The complete cp genome was 158,795 bp in length, consisting of a pair of inverted repeats of 26,587 bp, a large single-copy region of 87,233 bp and a small single-copy region of 18,388 bp. The genome encoded 113 unique genes, including 79 protein-coding genes, 30 tRNA genes and four rRNA genes. Phylogenetic analysis based on 16 complete cp genome sequences indicated that D. sinicus is a member of Huerteales, consistent with its position in the latest classification of flowering plants (AGP IV).


Assuntos
Proteínas de Cloroplastos/genética , Cloroplastos/genética , DNA de Cloroplastos/genética , Genoma de Cloroplastos , Magnoliopsida/genética , Magnoliopsida/classificação , Sequenciamento Completo do Genoma
14.
Mol Biotechnol ; 61(6): 461-468, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30997667

RESUMO

Synthetic biology and genetic engineering in algae offer an unprecedented opportunity to develop species with traits that can help solve the problems associated with food and energy supply in the 21st century. In the green alga Chlamydomonas reinhardtii, foreign genes can be expressed from the chloroplast genome for molecular farming and metabolic engineering to obtain commodities and high-value molecules. To introduce these genes, selectable markers, which rely mostly on the use of antibiotics, are needed. This has risen social concern associated with the potential risk of horizontal gene transfer across life kingdoms, which has led to a quest for antibiotic-free selectable markers. Phosphorus (P) is a scarce nutrient element that most organisms can only assimilate in its most oxidized form as phosphate (Pi); however, some organisms are able to oxidize phosphite (Phi) to Pi prior to incorporation into the central metabolism of P. As an alternative to the use of the two positive selectable makers already available for chloroplast transformation in C. reinhardtii, the aadA and the aphA-6 genes, that require the use of antibiotics, we investigated if a phosphite-based selection method could be used for the direct recovery of chloroplast transformed lines in this alga. Here we show that following bombardment with a vector carrying the ptxD gene from Pseudomonas stutzeri WM88, only cells that integrate and express the gene proliferate and form colonies using Phi as the sole P source. Our results demonstrate that a selectable marker based on the assimilation of Phi can be used for chloroplasts transformation in a biotechnologically relevant organism. The portable selectable marker we have developed is, in more than 18 years, the latest addition to the markers available for selection of chloroplast transformed cells in C. reinhardtii. The ptxD gene will contribute to the repertoire of tools available for synthetic biology and genetic engineering in the chloroplast of C. reinhardtii.


Assuntos
Proteínas de Bactérias/genética , Chlamydomonas reinhardtii/genética , Cloroplastos/genética , NADH NADPH Oxirredutases/genética , Fosfitos/metabolismo , Fósforo/metabolismo , Proteínas de Algas/genética , Proteínas de Algas/metabolismo , Proteínas de Bactérias/metabolismo , Chlamydomonas reinhardtii/metabolismo , Cloroplastos/metabolismo , Engenharia Genética/métodos , Marcadores Genéticos , Vetores Genéticos/química , Vetores Genéticos/metabolismo , NADH NADPH Oxirredutases/metabolismo , Fosfitos/farmacologia , Pseudomonas stutzeri/química , Pseudomonas stutzeri/genética , Seleção Genética , Transformação Genética
15.
Biol Bull ; 236(2): 88-96, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30933641

RESUMO

Sacoglossan sea slugs feed by suctorially consuming siphonaceous green algae. Most sacoglossan species are feeding specialists, but the Caribbean coral reef-dwelling Elysia crispata is polyphagous and sequesters chloroplasts from multiple algal species into cells lining its digestive diverticulum for use in photosynthesis. We have used sequences of the chloroplast-encoded rbcL gene to compare the chloroplast donor algae in five populations of E. crispata from various Caribbean locations. We found that E. crispata utilizes more algal species than was previously known, including some algae previously not reported as present in the region. In addition, slugs from each location had unique chloroplast arrays with little overlap, except that all locations had slugs feeding on algae within the genus Bryopsis. This variation in diet between locations suggests that the slugs may be exhibiting local adaptation in their dietary choices, and it highlights ecological differences between the Caribbean-wide reef-dwelling ecotypes and the mangrove lagoon ecotypes found in the Florida Keys.


Assuntos
Clorófitas/classificação , Cloroplastos/classificação , Gastrópodes/fisiologia , Animais , Região do Caribe , Clorófitas/genética , Cloroplastos/genética , Dieta , Ecossistema , Fotossíntese , Análise de Sequência de DNA
16.
Biomed Res Int ; 2019: 5046958, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31016191

RESUMO

Sorghum comprises 31 species that exhibit considerable morphological and ecological diversity. The phylogenetic relationships among Sorghum species still remain unresolved due to lower information on the traditional DNA markers, which provides a limited resolution for identifying Sorghum species. In this study, we sequenced the complete chloroplast genomes of Sorghum sudanense and S. propinquum and analyzed the published chloroplast genomes of S. bicolor and S. timorense to retrieve valuable chloroplast molecular resources for Sorghum. The chloroplast genomes ranged in length from 140,629 to 140,755 bp, and their gene contents, gene orders, and GC contents were similar to those for other Poaceae species but were slightly different in the number of SSRs. Comparative analyses among the four chloroplast genomes revealed 651 variable sites, 137 indels, and nine small inversions. Four highly divergent DNA regions (rps16-trnQ, trnG-trnM, rbcL-psaI, and rps15-ndhF), which were suitable for phylogenetic and species identification, were detected in the Sorghum chloroplast genomes. A phylogenetic analysis strongly supported that Sorghum is a monophyletic group in the tribe Andropogoneae. Overall, the genomic resources in this study could provide potential molecular markers for phylogeny and species identification in Sorghum.


Assuntos
Cloroplastos/genética , Genoma de Cloroplastos/genética , Sorghum/genética , Composição de Bases/genética , DNA de Cloroplastos/genética , Ordem dos Genes/genética , Marcadores Genéticos/genética , Genômica/métodos , Filogenia , Poaceae/genética , Análise de Sequência de DNA/métodos
17.
Nucleic Acids Res ; 47(7): 3344-3352, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30828719

RESUMO

While bacterial operons have been thoroughly studied, few analyses of chloroplast operons exist, limiting the ability to study fundamental elements of these structures and utilize them for synthetic biology. Here, we describe the creation of a plastome-specific operon database (link provided below) achieved by combining experimental tools and predictive modeling. Using a Reverse-Transcription-PCR based method and published data, we determined the transcription-state of 213 gene pairs from four plastomes of evolutionary distinct organisms. By analyzing sequence-based features computed for our dataset, we were able to highlight fundamental characteristics differentiating between operon pairs and non-operon pairs. These include an interesting tendency toward maintaining similar messenger RNA-folding profiles in operon gene pairs, a feature that failed to yield any informative separation in cyanobacteria, suggesting that it catches unique traits of operon gene expression, which have evolved post-endosymbiosis. Subsequently, we used this feature set to train a random-forest classifier for operon prediction. As our results demonstrate the ability of our predictor to obtain accurate (84%) and robust predictions on unlabeled datasets, we proceeded to building operon maps for 2018 sequenced plastids. Our database may now present new opportunities for promoting metabolic engineering and synthetic biology in chloroplasts.


Assuntos
Algoritmos , Evolução Molecular , Óperon/genética , Plantas/genética , Plastídeos/genética , RNA de Plantas/genética , Cloroplastos/genética , Bases de Dados Genéticas , Conjuntos de Dados como Assunto , Árvores de Decisões , Engenharia Metabólica , Plantas/classificação , Dobramento de RNA , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Genética
18.
Int J Mol Sci ; 20(6)2019 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-30884842

RESUMO

Photosynthetic properties and transcriptomic profiles of green and white sectors of Ficus microcarpa (c.v. milky stripe fig) leaves were examined in naturally variegated plants. An anatomic analysis indicated that chloroplasts of the white sectors contained a higher abundance of starch granules and lacked stacked thylakoids. Moreover, no photosynthetic rate was detected in the white sectors. Transcriptome profile and differential expressed gene (DEG) analysis showed that genes encoding PSII core proteins were down-regulated in the white sectors. In genes related to chlorophyll metabolism, no DEGs were identified in the biosynthesis pathway of chlorophyll. However, genes encoding the first step of chlorophyll breakdown were up-regulated. The repression of genes involved in N-assimilation suggests that the white sectors were deprived of N. The mutation in the transcription factor mitochondrial transcription termination factor (mTERF) suggests that it induces colorlessness in leaves of the milky stripe fig.


Assuntos
Ficus/genética , Fotossíntese/genética , Proteínas de Plantas/genética , Transcriptoma/genética , Arabidopsis/genética , Hidrolases de Éster Carboxílico/genética , Clorofila/genética , Cloroplastos/genética , Ficus/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Proteólise , Tilacoides/genética
19.
Molecules ; 24(6)2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30875988

RESUMO

The genus Angelica (Apiaceae) comprises valuable herbal medicines. In this study, we determined the complete chloroplast (CP) genome sequence of A. polymorpha and compared it with that of Ligusticum officinale (GenBank accession no. NC039760). The CP genomes of A. polymorpha and L. officinale were 148,430 and 147,127 bp in length, respectively, with 37.6% GC content. Both CP genomes harbored 113 unique functional genes, including 79 protein-coding, four rRNA, and 30 tRNA genes. Comparative analysis of the two CP genomes revealed conserved genome structure, gene content, and gene order. However, highly variable regions, sufficient to distinguish between A. polymorpha and L. officinale, were identified in hypothetical chloroplast open reading frame1 (ycf1) and ycf2 genic regions. Nucleotide diversity (Pi) analysis indicated that ycf4⁻chloroplast envelope membrane protein (cemA) intergenic region was highly variable between the two species. Phylogenetic analysis revealed that A. polymorpha and L. officinale were well clustered at family Apiaceae. The ycf4-cemA intergenic region in A. polymorpha carried a 418 bp deletion compared with L. officinale. This region was used for the development of a novel indel marker, LYCE, which successfully discriminated between A. polymorpha and L. officinale accessions. Our results provide important taxonomic and phylogenetic information on herbal medicines and facilitate their authentication using the indel marker.


Assuntos
Angelica/classificação , Genoma de Cloroplastos , Ligusticum/classificação , Sequenciamento Completo do Genoma/métodos , Angelica/genética , Composição de Bases , Cloroplastos/genética , DNA Intergênico , Evolução Molecular , Ordem dos Genes , Tamanho do Genoma , Mutação INDEL , Ligusticum/genética , Fases de Leitura Aberta , Filogenia
20.
Planta ; 249(6): 1963-1975, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30900084

RESUMO

MAIN CONCLUSION: Plastid genome engineering is an effective method to generate drought-resistant potato plants accumulating glycine betaine in plastids. Glycine betaine (GB) plays an important role under abiotic stress, and its accumulation in chloroplasts is more effective on stress tolerance than that in cytosol of transgenic plants. Here, we report that the codA gene from Arthrobacter globiformis, which encoded choline oxidase to catalyze the conversion of choline to GB, was successfully introduced into potato (Solanum tuberosum) plastid genome by plastid genetic engineering. Two independent plastid-transformed lines were isolated and confirmed as homoplasmic via Southern-blot analysis, in which the mRNA level of codA was much higher in leaves than in tubers. GB accumulated in similar levels in both leaves and tubers of codA-transplastomic potato plants (referred to as PC plants). The GB content was moderately increased in PC plants, and compartmentation of GB in plastids conferred considerably higher tolerance to drought stress compared to wild-type (WT) plants. Higher levels of relative water content and chlorophyll content under drought stress were detected in the leaves of PC plants compared to WT plants. Moreover, PC plants presented a significantly higher photosynthetic performance as well as antioxidant enzyme activities during drought stress. These results suggested that biosynthesis of GB by chloroplast engineering was an effective method to increase drought tolerance.


Assuntos
Oxirredutases do Álcool/metabolismo , Arthrobacter/enzimologia , Betaína/metabolismo , Solanum tuberosum/enzimologia , Oxirredutases do Álcool/genética , Arthrobacter/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cloroplastos/enzimologia , Cloroplastos/genética , Secas , Engenharia Genética , Fotossíntese , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas , Plastídeos/enzimologia , Plastídeos/genética , Solanum tuberosum/genética , Solanum tuberosum/fisiologia , Estresse Fisiológico
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