The phloem of dicotyledonous plants contains specialized P-proteins (phloem proteins) that accumulate during sieve element differentiation and remain parietally associated with the cisternae of the endoplasmic reticulum in mature sieve elements. Wounding causes P-protein filaments to accumulate at the sieve plates and block the translocation of photosynthate. Specialized, spindle-shaped P-proteins known as forisomes that undergo reversible calcium-dependent conformational changes have evolved exclusively in the Fabaceae. Recently, the molecular characterization of three genes encoding forisome components in the model legume Medicago truncatula (MtSEO1, MtSEO2 and MtSEO3; SEO = sieve element occlusion) was reported, but little is known about the molecular characteristics of P-proteins in non-Fabaceae.

With at least 60% of the Millettia species (Fabaceae) being in medicinal use, we found it relevant to assess the potential antiprotozoal and antifungal activities of Millettia richardiana. Water and methanol crude extracts of the stem barks from M. richardiana and the six fractions resulting from the fractionation of the methanol extract were tested. The dichloromethane extracted fraction showed the best in vitro antiprotozoal activities (IC50=5.8 μg/mL against Plasmodium falciparum, 11.8 μg/mL against Leishmania donovani and 12.8 μg/mL against Trypanosoma brucei brucei) as well as low cytotoxicity on several cell lines. The phytochemical analysis showed this selected fraction to be rich in terpenoids and alkaloids, which could explain its antiparasitic activity. A phytochemical study revealed the presence of lonchocarpenin, betulinic acid, β-amyrin, lupeol, palmitic acid, linoleic acid and stearic acid, among which betulinic acid and lupeol could be the compounds responsible of these antiprotozoal activities. By contrast, neither the crude extracts nor the fractions showed antifungal activity against Candida. These results confirm the importance of the genus Millettia in Malagasy ethnomedicine, its potential use in antiparasitic therapy, and the interest of developing a sustainable exploitation of this plant. Moreover, both molecules betulinic acid and lupeol appeared as very relevant molecules for their antiprotozoal properties.

Recent plastid genome (plastome) studies of legumes (family Fabaceae) have shown that this family has undergone multiple atypical plastome evolutions from each of the major clades. The tribe Desmodieae belongs to the Phaseoloids, an important but systematically puzzling clade within Fabaceae. In this study, we investigated the plastome evolution of Desmodieae and analyzed its phylogenetic signaling. We sequenced six complete plastomes from representative members of Desmodieae and from its putative sister Phaseoloid genus Mucuna. Those genomes contain 128 genes and range in size from 148,450 to 153,826 bp. Analyses of gene and intron content revealed similar characters among the members of Desmodieae and Mucuna. However, there were also several distinct characters identified. The loss of the rpl2 intron was a feature shared between Desmodieae and Mucuna, whereas the loss of the rps12 intron was specific to Desmodieae. Likewise, gene loss of rps16 was observed in Mucuna but not in Desmodieae. Substantial sequence variation of ycf4 was detected from all the sequenced plastomes, but pseudogenization was restricted to the genus Desmodium. Comparative analysis of gene order revealed a distinct plastome conformation of Desmodieae compared with other Phaseoloid legumes, i.e., an inversion of an approximately 1.5-kb gene cluster (trnD-GUC, trnY-GUA, and trnE-UUC). The inversion breakpoint suggests that this event was mediated by the recombination of an 11-bp repeat motif. A phylogenetic analysis based on the plastome-scale data set found the tribe Desmodieae is a highly supported monophyletic group nested within the paraphyletic Phaseoleae, as has been found in previous phylogenetic studies. Two subtribes (Desmodiinae and Lespedezinae) of Desmodieae were also supported as monophyletic groups. Within the subtribe Lespedezinae, Lespedeza is closer to Kummerowia than Campylotropis.

Aganope is a genus in the family Fabaceae, with only 11 species. They are distributed throughout Asia and Africa. Aganope dinghuensis, a newly reported species, is native to China with a restricted distribution. We, therefore, report its complete chloroplast genome for better future conservation. The chloroplast genome of A. dinghuensis is 143,690 bp, with a GC content of 35.32%. In the genome, a pair of inverted repeat regions of 13,015 bp each, a large single-copy region of 98,824 bp, and a small single-copy region of 18,836 bp were identified. Genome annotation identified 115 genes, comprising 74 protein-coding genes, 8 ribosomal RNA genes, and 33 transfer RNA genes. Repeat analysis indicates that the chloroplast genome of A. dinghuensis contains 126 simple sequence repeats (SSR), of which the majority are A/T mononucleotides. Phylogenetic analysis revealed that A. dinghuensis is a sister to the clade that includes Indigofera tinctoria, Desmodium uncinatum, Sarcodum scandens, Wisteria brachybotrys, and Callerya nitida.

Ormosia purpureiflora is endemic to China. It is named after its purple flowers. It is a small tree only up to 3 m. It has leathery leaves, racemose inflorescences. The seeds are elliptic and red in coat. It is only confined to Luofushan Provincial Nature Reserve in Huizhou of Guangdong Province. Herein, we first reported on its complete chloroplast genome sequence as genomic resource for conservation purposes. The chloroplast genome of O. purpureiflora was 173,364 bp in length, with a large single-copy region of 73,465 bp, a small single-copy region of 18,751 bp, and a pair of inverted repeat regions that were 40,574 bp each. A total of 90 protein-coding genes, 38 transfer RNA genes, and eight ribosomal RNA genes were predicted, while 106 simple sequence repeats were recorded throughout the genome. Phylogenetic analysis revealed that O. purpureiflora was sister to O. emarginata.

Microsatellite loci were developed for the understudied root crop yam bean (Pachyrhizus spp.) to investigate intraspecific diversity and interspecific relationships within the genus Pachyrhizus. •

Microsatellite primers were developed for the rare shrub Acacia adinophylla (Fabaceae) to assess genetic diversity and its spatial structuring.

The genus Trifolium L. is characterized by basic chromosome numbers 8, 7, 6, and 5. We conducted a genus-wide study of ribosomal DNA (rDNA) structure variability in diploids and polyploids to gain insight into evolutionary history. We used fluorescent in situ hybridization to newly investigate rDNA variation by number and position in 30 Trifolium species. Evolutionary history among species was examined using 85 available sequences of internal transcribed spacer 1 (ITS1) of 35S rDNA. In diploid species with ancestral basic chromosome number (x = 8), one pair of 5S and 26S rDNA in separate or adjacent positions on a pair of chromosomes was prevalent. Genomes of species with reduced basic chromosome numbers were characterized by increased number of signals determined on one pair of chromosomes or all chromosomes. Increased number of signals was observed also in diploids Trifolium alpestre and Trifolium microcephalum and in polyploids. Sequence alignment revealed ITS1 sequences with mostly single nucleotide polymorphisms, and ITS1 diversity was greater in diploids with reduced basic chromosome numbers compared to diploids with ancestral basic chromosome number (x = 8) and polyploids. Our results suggest the presence of one 5S rDNA site and one 26S rDNA site as an ancestral state.

Senna spectabilis var. excelsa (Fabaceae) is a South and Central American tree of great ecological importance and one of the most common species in several sites of seasonally dry forests. Our goal was to develop microsatellite markers to assess the genetic diversity and structure of this species.

The complete chloroplast genome of Mucuna sempervirens reported herein was a circular DNA molecule of 154,542 bp in length. The genome had a typical quadripartite structure, consisting of a pair of inverted repeats (IRa and IRb: 24,836 bp) separated by a large single-copy region (LSC: 67,996 bp) and a small single-copy region (SSC: 18,363 bp). The overall GC content of the genome was 35.1%. The cp genome encoded a set of 128 genes, containing 82 protein-coding genes, 37 tRNA genes, and eight rRNA genes. Phylogenetic analysis indicated that M. sempervirens was sister to M. macrocarpa. These findings may provide useful information to the phylogeny of the genus Mucuna.

Uraria Desv. belongs to the tribe Desmodieae (Fabaceae), a group of legume plants, some of which have medicinal properties. However, due to a lack of genomic information, the interspecific relationships, genetic diversity, population genetics, and identification of functional genes within Uraria species are still unclear.

Acacia crassicarpa (Fabaceae), a nitrogen-fixing tree species, is critically important for coastal protection in southeast China. In this study, we report the complete chloroplast genome sequence of A. crassicarpa, with a length of 176,493 bp. It contains a pair of inverted repeats (IR 39,851 bp), a large single-copy region (LSC 91,869 bp), and a small single-copy region (SSC 4,922 bp). The complete genome comprises 138 genes, including 93 protein-coding genes, 37 tRNA, and 8 rRNA genes. Our phylogenetic analysis reveals that A. crassicarpa is closely related to A. podalyriifolia and A. dealbata.

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Here we describe Oxytropis shennongjiaensis, a new species of Fabaceae from Central China (Hubei Province). Morphologically, O. shennongjiaensis is closely similar to O. sitaipaiensis, O. melanocalyx and O. kansuensis, but differs in stem characters, with less conspicuous internodes; persistent herbaceous stipules; pale yellow to white corolla; and stipitate legumes, 3-5 mm with a long beak. Phylogenetic analysis, based on the internal transcribed spacers (ITS) and two chloroplast markers (trnL-F and psbA-trnH), also identified O. shennongjiaensis as a new species, which is consistent with our morphological analyses. Considering the morphological data and phylogenetic data presented here, we believe that this evidence satisfies the required diagnostic criteria to identify O. shennongjiaensis as a new species.

Astragalus galactites is a medicinal plant. The total plastome length of A. galactites is 126,117 bp. It contains a large single-copy region of 69,805 bp, two inverted repeat regions of 20,638 bp, and a small single-copy region of 15,036 bp. The cp genome contains 110 complete genes, including 75 protein-coding genes (75 PCGs), 4 ribosomal RNA genes (4 rRNAs), and 30 tRNA genes (30 tRNAs). The overall GC content of cp DNA is 33.9%, the corresponding values of the LSC, SSC, and IR regions are 33.0%, 30.4%, and 43.3% respectively. The phylogenetic tree shows that A. galactites has the closest relationship with A. laxmannii.

The plastid genomes of photosynthetic green plants have largely maintained conserved gene content and order as well as structure over hundreds of millions of years of evolution. Several plant lineages, however, have departed from this conservation and contain many plastome structural rearrangements, which have been associated with an abundance of repeated sequences both overall and near rearrangement endpoints. We sequenced the plastomes of 25 taxa of Astragalus L. (Fabaceae), a large genus in the inverted repeat-lacking clade of legumes, to gain a greater understanding of the connection between repeats and plastome inversions. We found plastome repeat structure has a strong phylogenetic signal among these closely related taxa mostly in the New World clade of Astragalus called Neo-Astragalus. Taxa without inversions also do not differ substantially in their overall repeat structure from four taxa each with one large-scale inversion. For two taxa with inversion endpoints between the same pairs of genes, differences in their exact endpoints indicate the inversions occurred independently. Our proposed mechanism for inversion formation suggests the short inverted repeats now found near the endpoints of the four inversions may be there as a result of these inversions rather than their cause. The longer inverted repeats now near endpoints may have allowed the inversions first mediated by shorter microhomologous sequences to propagate, something that should be considered in explaining how any plastome rearrangement becomes fixed regardless of the mechanism of initial formation.

The arthropod-borne Mayaro virus (MAYV) causes 'Mayaro fever', a disease of medical significance, primarily affecting individuals in permanent contact with forested areas in tropical South America. Studies showed that the virus could also be transmitted by the mosquito Aedes aegypti. Recently, MAYV has attracted attention due to its likely urbanization. To date, there are no drugs that can treat this illness.

The first complete chloroplast genome of Oxytropis bicolor Bunge is reported and characterized in this study. The whole chloroplast genome was 122,461 base pairs in length with 110 genes, including 76 protein-coding genes, 30 tRNAs, and 4 rRNAs. In addition, the atpF intron was absent. Maximum-likelihood (ML) phylogenetic analysis indicated that O. bicolor and species of Astragalus were closely related, which is congruent with previous studies.

Microsatellite primers were developed for a perennial legume from northern China, Oxytropis diversifolia (Fabaceae), to investigate population genetic structure of this taxon, as well as potential hybridization events with closely related taxa in this genus.

Twelve species of wild leguminosae were studied to determine similarities in the coat details of the seeds using a Scanning Electron Microscope (SEM). The numerical cluster analysis method was used to examine the morphological characteristics (98 characteristics) and to clarify the taxonomic relationship between the studied species (6 genera and 3 tribes) belonging to the Fabaceae family. The relevant wild species were: Lotus edulis L, Lotus ornithopodioides L., Tetragonolobus purpureus Moench, Medicago laciniata (L.) Mill., Gard. Dict., M.orbicularis (L.) Bart., M.turbinata (L.) All, M.polymorpha L., Ononis vaginalis Vahl, Lathyrus aphaca L., Vicia sativa L., V. peregrine L., and V.tetrasperma (L.) Schreb. The aim of this study was to produce a taxonomy reflecting the relations between these twelve forage species of Fabaceae by using the morphological and SEM features to provide a details about and clarify the relations between the examined taxa. The taxonomic histories of the Fabaceae family were reviewed. The results of the morphological description and SEM showed that it was possible to distinguish between the taxa using the cluster analysis attributes for the differences in characteristic correlation between the groups under study. This study will help researchers better grasp the classification of these species of legumes which were chosen because of the difficulty of differentiating between them, their environment benefits, their use for human consumption and pasture. The SEM is a suitable tool for this analysis, owing to the similarities exhibited by the seeds.