Characterization of chloroplast genomes of Alnus rubra and Betula cordifolia, and their use in phylogenetic analyses in Betulaceae

Fructans are fructose-based (poly)saccharides with inulin and levan being the best-known ones. Thanks to their health-related benefits, inulin-type fructans have been under the focus of scientific and industrial communities, though mostly represented by plant-based inulins, and rarely by microbial ones. Recently, it was discovered that some extremely halophilic Archaea are also able to synthesize fructans. Here, we describe the first in-depth functional and molecular characterization of an Archaeal inulosucrase from Halomicrobium sp. IBSBa (HmcIsc). The HmcIsc enzyme was recombinantly expressed and purified in Escherichia coli and shown to synthesize inulin as proven by nuclear magnetic resonance (NMR) analysis. In accordance with the halophilic lifestyle of its native host, the enzyme showed maximum activity at very high NaCl concentrations (3.5 M), with specific adaptations for that purpose. Phylogenetic analyses suggested that Archaeal inulosucrases have been acquired from halophilic bacilli through horizontal gene transfer, with a HX(H/F)T motif evolving further into a HXHT motif, together with a unique D residue creating the onset of a specific alternative acceptor binding groove. This work uncovers a novel area in fructan research, highlighting unexplored aspects of life in hypersaline habitats, and raising questions about the general physiological relevance of inulosucrases and their products in nature.

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Organelle Genetics in Plants

International Journal of Molecular Sciences ◽

10.3390/ijms22042104 ◽

2021 ◽

Vol 22 (4) ◽

pp. 2104

Author(s):

Pedro Robles ◽

Víctor Quesada

Keyword(s):

Rna Editing ◽

Posttranscriptional Regulation ◽

Genome Engineering ◽

Plant Mitochondria ◽

Plastid Dna ◽

Chloroplast Genomes ◽

Wide Range ◽

Organelle Genetics ◽

Selection Of

Eleven published articles (4 reviews, 7 research papers) are collected in the Special Issue entitled “Organelle Genetics in Plants.” This selection of papers covers a wide range of topics related to chloroplasts and plant mitochondria research: (i) organellar gene expression (OGE) and, more specifically, chloroplast RNA editing in soybean, mitochondria RNA editing, and intron splicing in soybean during nodulation, as well as the study of the roles of transcriptional and posttranscriptional regulation of OGE in plant adaptation to environmental stress; (ii) analysis of the nuclear integrants of mitochondrial DNA (NUMTs) or plastid DNA (NUPTs); (iii) sequencing and characterization of mitochondrial and chloroplast genomes; (iv) recent advances in plastid genome engineering. Here we summarize the main findings of these works, which represent the latest research on the genetics, genomics, and biotechnology of chloroplasts and mitochondria.

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Comparative Chloroplast Genomics of Litsea Lam. (Lauraceae) and Its Phylogenetic Implications

Forests ◽

10.3390/f12060744 ◽

2021 ◽

Vol 12 (6) ◽

pp. 744

Author(s):

Yunyan Zhang ◽

Yongjing Tian ◽

David Y. P. Tng ◽

Jingbo Zhou ◽

Yuntian Zhang ◽

...

Keyword(s):

Chloroplast Genome ◽

Phylogenetic Analyses ◽

Eastern China ◽

Chloroplast Microsatellites ◽

Endangered Tree ◽

Protein Coding ◽

Intergenic Spacers ◽

Chloroplast Genomes ◽

Phylogenetic Implications ◽

Chloroplast Genome Sequence

Litsea Lam. is an ecological and economic important genus of the “core Lauraceae” group in the Lauraceae. The few studies to date on the comparative chloroplast genomics and phylogenomics of Litsea have been conducted as part of other studies on the Lauraceae. Here, we sequenced the whole chloroplast genome sequence of Litsea auriculata, an endangered tree endemic to eastern China, and compared this with previously published chloroplast genome sequences of 11 other Litsea species. The chloroplast genomes of the 12 Litsea species ranged from 152,132 (L. szemaois) to 154,011 bp (L. garrettii) and exhibited a typical quadripartite structure with conserved genome arrangement and content, with length variations in the inverted repeat regions (IRs). No codon usage preferences were detected within the 30 codons used in the chloroplast genomes, indicating a conserved evolution model for the genus. Ten intergenic spacers (psbE–petL, trnH–psbA, petA–psbJ, ndhF–rpl32, ycf4–cemA, rpl32–trnL, ndhG–ndhI, psbC–trnS, trnE–trnT, and psbM–trnD) and five protein coding genes (ndhD, matK, ccsA, ycf1, and ndhF) were identified as divergence hotspot regions and DNA barcodes of Litsea species. In total, 876 chloroplast microsatellites were located within the 12 chloroplast genomes. Phylogenetic analyses conducted using the 51 additional complete chloroplast genomes of “core Lauraceae” species demonstrated that the 12 Litsea species grouped into four sub-clades within the Laurus-Neolitsea clade, and that Litsea is polyphyletic and closely related to the genera Lindera and Laurus. Our phylogeny strongly supported the monophyly of the following three clades (Laurus–Neolitsea, Cinnamomum–Ocotea, and Machilus–Persea) among the above investigated “core Lauraceae” species. Overall, our study highlighted the taxonomic utility of chloroplast genomes in Litsea, and the genetic markers identified here will facilitate future studies on the evolution, conservation, population genetics, and phylogeography of L. auriculata and other Litsea species.

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Chloroplast genome variation and phylogenetic relationships of Atractylodes species

BMC Genomics ◽

10.1186/s12864-021-07394-8 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Yiheng Wang ◽

Sheng Wang ◽

Yanlei Liu ◽

Qingjun Yuan ◽

Jiahui Sun ◽

...

Keyword(s):

Chloroplast Genome ◽

High Throughput Sequencing ◽

Phylogenetic Analyses ◽

Herbal Medicines ◽

Structural Genomic ◽

Protein Coding ◽

Chloroplast Genomes ◽

Original Plant ◽

Morphological Differences ◽

Rna Genes

Abstract Background Atractylodes DC is the basic original plant of the widely used herbal medicines “Baizhu” and “Cangzhu” and an endemic genus in East Asia. Species within the genus have minor morphological differences, and the universal DNA barcodes cannot clearly distinguish the systemic relationship or identify the species of the genus. In order to solve these question, we sequenced the chloroplast genomes of all species of Atractylodes using high-throughput sequencing. Results The results indicate that the chloroplast genome of Atractylodes has a typical quadripartite structure and ranges from 152,294 bp (A. carlinoides) to 153,261 bp (A. macrocephala) in size. The genome of all species contains 113 genes, including 79 protein-coding genes, 30 transfer RNA genes and four ribosomal RNA genes. Four hotspots, rpl22-rps19-rpl2, psbM-trnD, trnR-trnT(GGU), and trnT(UGU)-trnL, and a total of 42–47 simple sequence repeats (SSR) were identified as the most promising potentially variable makers for species delimitation and population genetic studies. Phylogenetic analyses of the whole chloroplast genomes indicate that Atractylodes is a clade within the tribe Cynareae; Atractylodes species form a monophyly that clearly reflects the relationship within the genus. Conclusions Our study included investigations of the sequences and structural genomic variations, phylogenetics and mutation dynamics of Atractylodes chloroplast genomes and will facilitate future studies in population genetics, taxonomy and species identification.

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Chloroplast genomes in Populus (Salicaceae): comparisons from an intensively sampled genus reveal dynamic patterns of evolution

Scientific Reports ◽

10.1038/s41598-021-88160-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jiawei Zhou ◽

Shuo Zhang ◽

Jie Wang ◽

Hongmei Shen ◽

Bin Ai ◽

...

Keyword(s):

Phylogenetic Analyses ◽

Population Level ◽

Gene Content ◽

Sequencing Data ◽

Cellular Functions ◽

Chloroplast Evolution ◽

Chloroplast Genomes ◽

Genome Features ◽

Genome Annotations ◽

Genome Analyses

AbstractThe chloroplast is one of two organelles containing a separate genome that codes for essential and distinct cellular functions such as photosynthesis. Given the importance of chloroplasts in plant metabolism, the genomic architecture and gene content have been strongly conserved through long periods of time and as such are useful molecular tools for evolutionary inferences. At present, complete chloroplast genomes from over 4000 species have been deposited into publicly accessible databases. Despite the large number of complete chloroplast genomes, comprehensive analyses regarding genome architecture and gene content have not been conducted for many lineages with complete species sampling. In this study, we employed the genus Populus to assess how more comprehensively sampled chloroplast genome analyses can be used in understanding chloroplast evolution in a broadly studied lineage of angiosperms. We conducted comparative analyses across Populus in order to elucidate variation in key genome features such as genome size, gene number, gene content, repeat type and number, SSR (Simple Sequence Repeat) abundance, and boundary positioning between the four main units of the genome. We found that some genome annotations were variable across the genus owing in part from errors in assembly or data checking and from this provided corrected annotations. We also employed complete chloroplast genomes for phylogenetic analyses including the dating of divergence times throughout the genus. Lastly, we utilized re-sequencing data to describe the variations of pan-chloroplast genomes at the population level for P. euphratica. The analyses used in this paper provide a blueprint for the types of analyses that can be conducted with publicly available chloroplast genomes as well as methods for building upon existing datasets to improve evolutionary inference.

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Molecular Characterization of PGC-1β (PPAR Gamma Coactivator 1β) and its Roles in Mitochondrial Biogenesis in Blunt Snout Bream (Megalobrama amblycephala)

International Journal of Molecular Sciences ◽

10.3390/ijms21061935 ◽

2020 ◽

Vol 21 (6) ◽

pp. 1935 ◽

Cited By ~ 1

Author(s):

Kangle Lu ◽

Tomas Policar ◽

Xiaojun Song ◽

Samad Rahimnejad

Keyword(s):

Molecular Characterization ◽

Mitochondrial Biogenesis ◽

Phylogenetic Analyses ◽

Ppar Gamma ◽

Megalobrama Amblycephala ◽

Fat Intake ◽

High Fat ◽

Blunt Snout Bream ◽

Mitochondria Biogenesis

This study aimed at achieving the molecular characterization of peroxisome proliferator-activated receptor-gamma coactivator 1β (PGC-1β) and exploring its modulatory roles in mitochondria biogenesis in blunt snout bream (Megalobrama amblycephala). A full-length cDNA of PGC-1β was cloned from liver which covered 3110 bp encoding 859 amino acids. The conserved motifs of PGC-1β family proteins were gained by MEME software, and the phylogenetic analyses showed motif loss and rearrangement of PGC-1β in fish. The function of PGC-1β was evaluated through overexpression and knockdown of PGC-1β in primary hepatocytes of blunt snout bream. We observed overexpression of PGC-1β along with enhanced mitochondrial transcription factor A (TFAM) expression and mtDNA copies in hepatocytes, and its knockdown led to slightly reduced NRF1 expression. However, knockdown of PGC-1β did not significantly influence TFAM expression or mtDNA copies. The alterations in mitochondria biogenesis were assessed following high-fat intake, and the results showed that it induces downregulation of PGC-1β. Furthermore, significant decreases in mitochondrial respiratory chain activities and mitochondria biogenesis were observed by high-fat intake. Our findings demonstrated that overexpression of PGC-1β induces the enhancement of TFAM expression and mtDNA amount but not NRF-1. Therefore, it could be concluded that PGC-1β is involved in mitochondrial biogenesis in blunt snout bream but not through PGC-1β/NRF-1 pathway.

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Diversity unearthed by the estimated molecular phylogeny and ecologically quantitative characteristics of uncultured Ehrlichia bacteria in Haemaphysalis ticks, Japan

Scientific Reports ◽

10.1038/s41598-020-80690-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hongru Su ◽

Eri Onoda ◽

Hitoshi Tai ◽

Hiromi Fujita ◽

Shigetoshi Sakabe ◽

...

Keyword(s):

Phylogenetic Analysis ◽

16S Rrna ◽

Core Genome ◽

Phylogenetic Analyses ◽

Taxonomic Status ◽

Housekeeping Genes ◽

Pcr Screening ◽

Taxonomic Profiling ◽

Quantitative Characteristics

AbstractEhrlichia species are obligatory intracellular bacteria transmitted by arthropods, and some of these species cause febrile diseases in humans and livestock. Genome sequencing has only been performed with cultured Ehrlichia species, and the taxonomic status of such ehrlichiae has been estimated by core genome-based phylogenetic analysis. However, many uncultured ehrlichiae exist in nature throughout the world, including Japan. This study aimed to conduct a molecular-based taxonomic and ecological characterization of uncultured Ehrlichia species or genotypes from ticks in Japan. We first surveyed 616 Haemaphysalis ticks by p28-PCR screening and analyzed five additional housekeeping genes (16S rRNA, groEL, gltA, ftsZ, and rpoB) from 11 p28-PCR-positive ticks. Phylogenetic analyses of the respective genes showed similar trees but with some differences. Furthermore, we found that V1 in the V1–V9 regions of Ehrlichia 16S rRNA exhibited the greatest variability. From an ecological viewpoint, the amounts of ehrlichiae in a single tick were found to equal approx. 6.3E+3 to 2.0E+6. Subsequently, core-partial-RGGFR-based phylogenetic analysis based on the concatenated sequences of the five housekeeping loci revealed six Ehrlichia genotypes, which included potentially new Ehrlichia species. Thus, our approach contributes to the taxonomic profiling and ecological quantitative analysis of uncultured or unidentified Ehrlichia species or genotypes worldwide.

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New perspectives on Aspersentis Megarhynchus (Acanthocephala: Heteracanthocephalidae) from Notothenia Coriiceps Richardson (Nototheniidae) in the West Antarctic, with emended generic diagnosis

Journal of Helminthology ◽

10.1017/s0022149x2100016x ◽

2021 ◽

Vol 95 ◽

Author(s):

O.M. Amin ◽

R.A. Heckmann ◽

S. Dallarés ◽

M. Constenla ◽

N.Yu. Rubtsova ◽

...

Keyword(s):

Phylogenetic Analyses ◽

Original Description ◽

Generic Diagnosis ◽

West Antarctica ◽

Dorsal Wall ◽

West Antarctic ◽

Notothenia Coriiceps ◽

The Many ◽

Dorsal Position

Abstract A number of variable descriptive accounts of Aspersentis megarhynchus (von Linstow, 1892) Golvan, 1960 have been reported from specimens collected from many species of fish in various locations off Antarctic islands. We have described a new population from Notothenia coriiceps Richardson (Nototheniidae) off Galindez Island, West Antarctica, and features not previously reported, resolved the taxonomic controversies and nomenclature, and emended and updated the generic diagnosis taking into account the newly observed structures. These are depicted in microscopic images and include the outer spiral wall of the proboscis receptacle, the thicker dorsal wall of the receptacle compared to the ventral wall, parts of the female reproductive system, the separate cement gland ducts, the dorsal position of the male gonopore and more detail of proboscis hooks and trunk spines. It is surprising that the newly observed features were missed from the many descriptions of A. megarhynchus created since the original description. The variability in A. megarhynchus is noted with a comparison of the morphometrics of our specimens vs. those in six other descriptions. We also analysed the metal composition of hooks and spines using energy-dispersive X-ray analysis and concluded a molecular characterization of the species based on 18S DNA gene, with related phylogenetic analyses.

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