The complete chloroplast genome of Origanum vulgare L. (Lamiaceae)

Oregano (Origanum vulgare L., Lamiaceae) is a medicinal and aromatic plant maybe best known for flavouring pizza. New applications e.g. as natural antioxidants for food are emerging due to the plants' high antibacterial and antioxidant activity. The complete chloroplast (cp) genome of Origanum vulgare (GenBank/EBML/DDBJ accession number: JX880022) consists of 151,935 bp and includes a pair of inverted repeats (IR) of 25,527 bp separated by one small and one large single copy region (SSC and LSC) of 17,745 and 83,136 bp, respectively.     

De novo assembly and characterization of the complete chloroplast genome of radish (Raphanus sativus L.)

Radish (Raphanus sativus L.) is an edible root vegetable crop that is cultivated worldwide and whose genome has been sequenced. Here we report the complete nucleotide sequence of the radish cultivar WK10039 chloroplast (cp) genome, along with a de novo assembly strategy using whole genome shotgun sequence reads obtained by next generation sequencing. The radish cp genome is 153,368 bp in length and has a typical quadripartite structure, composed of a pair of inverted repeat regions (26,217 bp each), a large single copy region (83,170 bp), and a small single copy region (17,764 bp). The radish cp genome contains 87 predicted protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Sequence analysis revealed the presence of 91 simple sequence repeats (SSRs) in the radish cp genome.     

The complete chloroplast genome sequence of Taxus chinensis var. mairei (Taxaceae): loss of an inverted repeat region and comparative analysis with related species

Taxus chinensis var. mairei (Taxaceae) is a domestic variety of yew species in local China. This plant is one of the sources for paclitaxel, which is a promising antineoplastic chemotherapy drugs during the last decade. We have sequenced the complete nucleotide sequence of the chloroplast (cp) genome of T. chinensis var. mairei. The T. chinensis var. mairei cp genome is 129,513 bp in length, with 113 single copy genes and two duplicated genes (trnI-CAU, trnQ-UUG). Among the 113 single copy genes, 9 are intron-containing. Compared to other land plant cp genomes, the T. chinensis var. mairei cp genome has lost one of the large inverted repeats (IRs) found in angiosperms, fern, liverwort, and gymnosperm such as Cycas revoluta and Ginkgo biloba L. Compared to related species, the gene order of T. chinensis var. mairei has a large inversion of ~ 110 kb including 91 genes (from rps18 to accD) with gene contents unarranged. Repeat analysis identified 48 direct and 2 inverted repeats 30 bp long or longer with a sequence identity greater than 90%. Repeated short segments were found in genes rps18, rps19 and clpP. Analysis also revealed 22 simple sequence repeat (SSR) loci and almost all are composed of A or T.     

Characterization of the chloroplast genome sequence of oil palm (Elaeis guineensis Jacq.)

Oil palm (Elaeis guineensis Jacq.) is an economically important crop, which is grown for oil production. To better understand the molecular basis of oil palm chloroplasts, we characterized the complete chloroplast (cp) genome sequence obtained from 454 pyrosequencing. The oil palm cp genome is 156,973 bp in length consisting of a large single-copy region of?85,192 bp flanked on each side by inverted repeats of 27,071 bp with a small single-copy region of 17,639 bp joining the?repeats. The genome contains 112 unique genes: 79 protein-coding genes, 4 ribosomal RNA genes and 29 tRNA genes. By aligning the cp?genome sequence with oil palm cDNA sequences, we observed 18 non-silent and 10 silent RNA editing events among 19 cp protein-coding genes. Creation of an initiation codon by RNA editing in rpl2 has been reported in several monocots and was also found in the oil palm cp genome. Fifty common chloroplast protein-coding genes from 33 plant taxa were used to construct ML and MP?phylogenetic trees. Their topologies are similar and strongly support for the position of E. guineensis as the sister of closely related species Phoenix dactylifera in Arecaceae (palm families) of monocot subtrees.     

Complete chloroplast genome sequence of Elodea canadensis and comparative analyses with other monocot plastid genomes

Elodea canadensis is an aquatic angiosperm native to North America. It has attracted great attention due to its invasive nature when transported to new areas in its non-native range. We have determined the complete nucleotide sequence of the chloroplast (cp) genome of Elodea. Taxonomically Elodea is a basal monocot, and only few monocot cp genomes representing early lineages of monocots have been sequenced so far. The genome is a circular double-stranded DNA molecule 156,700bp in length, and has a typical structure with large (LSC 86,194bp) and small (SSC 17,810bp) single-copy regions separated by a pair of inverted repeats (IRs 26,348bp each). The Elodea cp genome contains 113 unique genes and 16 duplicated genes in the IR regions. A comparative analysis showed that the gene order and organization of the Elodea cp genome is almost identical to that of Amborella trichopoda, a basal angiosperm. The structure of IRs in Elodea is unique among monocot species with the whole cp genome sequenced. In Elodea and another monocot Lemna minor the borders between IRs and LSC are located upstream of rps19 gene and downstream of trnH-GUG gene, while in most monocots, IR has extended to include both trnH and rps19 genes. A phylogenetic analysis conducted using Bayesian method, based on the DNA sequences of 81 chloroplast genes from 17 monocot taxa provided support for the placement of Elodea together with Lemna as a basal monocot and the next diverging lineage of monocots after Acorales. In comparison with other monocots, the Elodea cp genome has gone through only few rearrangements or gene losses. IR of Elodea has a unique structure among the monocot species studied so far as its structure is similar to that of a basal angiosperm Amborella. This result together with phylogenetic analyses supports the placement of Elodea as a basal monocot to the next diverging lineage of monocots after Acorales. So far, only few cp genomes representing early lineages of monocots have been sequenced and, therefore, this study provides valuable information about the course of evolution in divergence of monocot lineages.     

Complete mitochondrial genome of the stonefly Cryptoperla stilifera Sivec (Plecoptera: Peltoperlidae) and the phylogeny of Polyneopteran insects

We present the complete mitogenome of a stonefly, Cryptoperla stilifera Sivec (Plecoptera; Peltoperlidae). The mitogenome was a circular molecule consisting of 15,633 nucleotides, 37 genes and a A + T-rich region. C. stilifera mitogenome was similar to Pteronarcys princeps mitogenome (Plecoptera; Pteronarcyidae). All transfer RNA genes (tRNAs) had typical cloverleaf secondary structures except for trnSer (AGN), where the stem-loop structure of the dihydrouridine (DHU) arm was missing. The A + T-rich region of C. stilifera had two stem-loops and each had two interlink. Three conserved sequence blocks (CSBs) were present in the A + T-rich regions of C. stilifera, Peltoperla tarteri and Peltoperla arcuata. Moreover, many polynucleotide stretches (Poly N, N = A, T and C) in the A + T-rich region of C. stilifera Phylogenetic relationships of Polyneopteran species were constructed based on the nucleotide sequences of 13 protein coding genes (PCGs). Both maximum likelihood (ML) and Bayesian inference (BI) analyses supported Grylloblattodea as the sister group to Plecoptera + Dermaptera and Embiidina and Phasmatodea as sister groups.     

Complete nucleotide sequence and gene organization of the mitochondrial genome of Paa spinosa (Anura: Ranoidae)

The mt genome of Paa spinosa (Anura: Ranoidae) is a circular molecule of 18,012 bp in length, containing 38 genes (including an extra copy of tRNA-Met gene). This mt genome is characterized by three distinctive features: a cluster of rearranged tRNA genes (LTPF tRNA gene cluster), a tandem duplication of tRNA-Met gene (Met1 and Met2), and distinct repeat regions at both 5′ and 3′-sides in the control region. Comparing the locations and the sequences of all tRNA-Met genes among Ranoidae, and constructing NJ tree of the nucleotide of those tRNA-Met genes, we suggested a tandem duplication of tRNA-Met gene can be regarded as a synapomorphy of Dicroglossinae. To further investigate the phylogenetic relationships of anurans, phylogenetic analyses (BI, ML and MP) based on the nucleotide dataset and the corresponding amino acid dataset of 11 protein-coding genes (except ND5 and ATP8) arrived at the similar topology.     

Complete mitochondrial genome sequences of three bats species and whole genome mitochondrial analyses reveal patterns of codon bias and lend support to a basal split in Chiroptera

Order Chiroptera is a unique group of mammals whose members have attained self-powered flight as their main mode of locomotion. Much speculation persists regarding bat evolution; however, lack of sufficient molecular data hampers evolutionary and conservation studies. Of ~ 1200 species, complete mitochondrial genome sequences are available for only eleven. Additional sequences should be generated if we are to resolve many questions concerning these fascinating mammals. Herein, we describe the complete mitochondrial genomes of three bats: Corynorhinus rafinesquii, Lasiurus borealis and Artibeus lituratus. We also compare the currently available mitochondrial genomes and analyze codon usage in Chiroptera. C. rafinesquii, L. borealis and A. lituratus mitochondrial genomes are 16438 bp, 17048 bp and 16709 bp, respectively. Genome organization and gene arrangements are similar to other bats. Phylogenetic analyses using complete mitochondrial genome sequences support previously established phylogenetic relationships and suggest utility in future studies focusing on the evolutionary aspects of these species. Comprehensive analyses of available bat mitochondrial genomes reveal distinct nucleotide patterns and synonymous codon preferences corresponding to different chiropteran families. These patterns suggest that mutational and selection forces are acting to different extents within Chiroptera and shape their mitochondrial genomes.     

The complete mitochondrial genome of Sasakia funebris (Leech) (Lepidoptera: Nymphalidae) and comparison with other Apaturinae insects

Sasakia funebris, a member of the lepidopteran family, Nymphalidae (superfamily Papilionoidea) is a rare species and is found only in some areas of South China. In this study, the 15,233 bp long complete mitochondrial genome of S. funebris was determined, and harbors the gene arrangement identical to all other sequenced lepidopteran insects. The nucleotide composition of the genome is highly A + T biased, accounting for 81.2%. All protein-coding genes (PCGs) start with typical ATN codons, except for COI which begins with the CGA codon. All tRNAs have a typical clover-leaf secondary structure, except for tRNA^Ser(AGN), the dihydrouridine (DHU) arm of which forms a simple loop. The S. funebris A + T-rich region of 370 bp contains several features common to the Lepidoptera insects, including the motif ATAGA followed by a 19 bp poly-T stretch, and two tandem repeats consisting of 18 bp repeat units and 14 bp repeat units. The phylogenetic analyses of Apaturinae based on mitogenome sequences showed: (S. funebris + Sasakia charonda) + (Apatura metis + Apatura ilia). This result is consistent with the morphological classification.     

Isolation and expression of cytochrome P450 genes in the antennae and gut of pine beetle Dendroctonus rhizophagus (Curculionidae: Scolytinae) following exposure to host monoterpenes

Bark beetles oxidize the defensive monoterpenes of their host trees both to detoxify them and convert them into components of their pheromone system. This oxidation is catalyzed by cytochrome P450 enzymes and occurs in different tissues of the insect, including the gut (i.e., the site where the beetle's pheromones are produced and accumulated) and the antennae (i.e., the olfactory organs used for perception of airborne defensive monoterpenes as well as other host-associated compounds and pheromones). We identified ten new CYP genes in the pine beetle Dendroctonus rhizophagus in either antennae or gut tissue after stimulation with the vapors of major host monoterpenes α-pinene, β-pinene and 3-carene. Five genes belong to the CYP4 family, four to the CYP6 family and one to the CYP9 family. Differential expression of almost all of the CYP genes was observed between sexes, and within these significant differences among time, stimuli, anatomical region, and their interactions were found upon exposure to host monoterpenes. Increased expression of cytochrome P450 genes suggests that they play a role in the detoxification of monoterpenes released by this insect's host trees.