The complete chloroplast genome sequence of three medicinal species; Curcuma longa, Curcuma wenyujin, and Curcuma phaeocaulis (Zingiberaceae).

Curcuma longa, C. wenyujin and C. phaeocaulis are important herbal medicine which of rhizomatous herbaceous perennial plant of the family Zingiberaceae. This study generated a complete chloroplast genome sequence of three medicinal species were characterized by de novo assembly with whole genome sequencing data. The length of complete chloroplast genome were 162,180 bp (C. longa), 162,266 bp (C. wenyujin), and 162,133 bp (C. phaeocaulis), respectively, with four structures that were included in large single copy region (87,001 bp, 87,042 bp, and 87,013 bp), small single copy region (15,681 bp, 15,710 bp, and 15,622 bp), and duplicated inverted regions (29,749 bp, 29,757 bp and 29,749 bp of each). Based on phylogenetic trees, C. longa, C. wenyujin, and C. phaeocaulis were grouped by high bootstrap value with Curcuma species. This result approved that C. longa, C. wenyujin and C. phaeocaulis were comprised in Alpinia and Wurfbainia. Therefore, this chloroplast genome data firstly generated valuable genetic resource in discrimination of herbal materials, phylogeny and development DNA marker.

Dynamic Chloroplast Genome Rearrangement and DNA Barcoding for Three Apiaceae Species Known as the Medicinal Herb "Bang-Poong".

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.

The complete chloroplast genome of the medicinal plant Angelica decursiva (Apiaceae) in Peucedani Radix.

Angelica decursiva (Miquel) Franchet & Savatier (Apiaceae) has been used as a significant medicinal plant in East Asia. We determined its complete chloroplast genome for the first time in this study. The complete chloroplast was circularized and had a typical quadripartite structure genome of 146 719 bp long including the large single copy region (LSC) of 93 256 bp, the small single copy region (SSC) of 17 497 bp and duplicated inverted regions (IRs) of 17 983 bp each. The total GC content was 37.56% and for the four structures it was 35.98% (LSC), 31.06% (SSC), and 44.83% (for each IR). There were a total of 113 genes, comprising four rRNAs, 29 tRNAs and 80 protein coding genes. In the phylogenetic analysis, A. decursiva was grouped with Seseli montanum. This study may contribute to authenticating the plant's correct use as medicine for health and provide an important genetic resource for phylogeny with related species.

The complete chloroplast genome sequence of Ostericum koreanum (Apiaceae).

Ostericum koreanum Kitagawa is an important herbal medicine, whose taxonomic status has been changed to Angelica reflexa as a new species. This study generated the complete chloroplast genome sequence of O. koreanum, and reconsidered its molecular taxonomic status in Angelica by comparing it with related species. The length of the complete chloroplast genome was 147,282 bp, and there were four structures that included the large single copy region (93,185 bp), the small single copy region (17,663 bp) and the duplicated inverted regions (18,217 bp of each). Based on its phylogenetic trees, O. koreanum was grouped by high bootstrap value with the Angelica species. This result proved that O. koreanum is included in Angelica. Therefore, this chloroplast genome data generated for the first time a valuable genetic resource for the discrimination of herbal materials, phylogeny, and evolution.

Population structure and domestication revealed by high-depth resequencing of Korean cultivated and wild soybean genomes.

Despite the importance of soybean as a major crop, genome-wide variation and evolution of cultivated soybeans are largely unknown. Here, we catalogued genome variation in an annual soybean population by high-depth resequencing of 10 cultivated and 6 wild accessions and obtained 3.87 million high-quality single-nucleotide polymorphisms (SNPs) after excluding the sites with missing data in any accession. Nuclear genome phylogeny supported a single origin for the cultivated soybeans. We identified 10-fold longer linkage disequilibrium (LD) in the wild soybean relative to wild maize and rice. Despite the small population size, the long LD and large SNP data allowed us to identify 206 candidate domestication regions with significantly lower diversity in the cultivated, but not in the wild, soybeans. Some of the genes in these candidate regions were associated with soybean homologues of canonical domestication genes. However, several examples, which are likely specific to soybean or eudicot crop plants, were also observed. Consequently, the variation data identified in this study should be valuable for breeding and for identifying agronomically important genes in soybeans. However, the long LD of wild soybeans may hinder pinpointing causal gene(s) in the candidate regions.

Dynamic genetic features of chromosomes revealed by comparison of soybean genetic and sequence-based physical maps.

Despite the intensive soybean [Glycine max (L.) Merrill] genome studies, the high chromosome number (20) of the soybean plant relative to many other major crops has hindered the development of a high-resolution genomewide genetic map derived from a single population. Here, we report such a map, which was constructed in an F15 population derived from a cross between G. max and G. soja lines using indel polymorphisms detected via a G. soja genome resequencing. By targeting novel indel markers to marker-poor regions, all marker intervals were reduced to under 6 cM on a genome scale. Comparison of the Williams 82 soybean reference genome sequence and our genetic map indicated that marker orders of 26 regions were discrepant with each other. In addition, our comparison showed seven misplaced and two absent markers in the current Williams 82 assembly and six markers placed on the scaffolds that were not incorporated into the pseudomolecules. Then, we showed that, by determining the missing sequences located at the presumed beginning points of the five major discordant segments, these observed discordant regions are mostly errors in the Williams 82 assembly. Distributions of the recombination rates along the chromosomes were similar to those of other organisms. Genotyping of indel markers and genome resequencing of the two parental lines suggested that some marker-poor chromosomal regions may represent introgression regions, which appear to be prevalent in soybean. Given the even and dense distribution of markers, our genetic map can serve as a bridge between genomics research and breeding programs.

Glycine max non-nodulation locus rj1: a recombinogenic region encompassing a SNP in a lysine motif receptor-like kinase (GmNFR1α).

The rj1 mutation of soybean is a simple recessive allele in a single line that arose as a spontaneous mutation in a population; it exhibits non-nodulation with virtually all Bradyrhizobium and Sinorhizobium strains. Here, we described fine genetic and physical mapping of the rj1 locus on soybean chromosome 2. The initial mapping of the rj1 locus using public markers indicated that A343.p2, a sequence-based marker that contains sequence similar to a part of the LjNFR1 gene regulating nodule formation as a member of lysin motif-type receptor-like kinase (LYK) family, maps very close to or cosegregates with the rj1 locus. The sequence of A343.p2 is 100% identical to parts of two BAC clone sequences (GM_WBb0002O19 and GM_WBb098N11) that contain three members of the LYK family. We analyzed the sequence contig (262 kbp) of the two BAC clones by resequencing and subsequent fine genetic and physical mapping. The results indicated that rj1 is located in a gene-rich region with a recombination rate of 120 kbp/cM: several fold higher than the genome average. Among the LYK genes, NFR1α is most likely the gene encoded at the Rj1 locus. The non-nodulating rj1 allele was created by a single base-pair deletion that results in a premature stop codon. Taken together, the fine genetic and physical mapping of the Rj1-residing chromosomal region, combined with the unexpected observation of a putative recombination hotspot, allowed us to demonstrate that the Rj1 locus most likely encodes the NFR1α gene.