Species Of Selaginella Research Articles

Biological Importance and Therapeutic Potential of Delicaflavone against Cancerous Disorders: A Rare Naturally Occurring Biflavonoids of Selaginella Species

Biological Importance and Therapeutic Potential of Delicaflavone against Cancerous Disorders: A Rare Naturally Occurring Biflavonoids of Selaginella Species

Selaginella pectopuellensis (Selaginellaceae, Lycopodiophyta): a new species from Serra do Peito-de-Moça, Bahia, Brazil, with comments on the taxonomy of the species reported in the country

Background and aims: Our research on neotropical Selaginella led us to examine a collection from the Atlantic Forest of Serra do Peito-de-Moça, Bahia, Brazil, initially determined as S. muscosa but with unusual features, indicating it represented an undescribed species. We also reexamined the taxonomic and nomenclatural status of three Selaginella taxa previously described from Brazil and gathered information on introduced and naturalized species in the country. M&M: Morphological analysis used stereomicroscopes and scanning electron microscopy to distinguish the suspected new species from its morphologically nearest ally. Results: We confirmed that the plant material from the Atlantic Forest of Serra do Peitode-Moça, Bahia, Brazil, is a new species that we named Selaginella pectopuellensis (Selaginellaceae). Additionally, we clarified the taxonomic and nomenclatural status of three Selaginella species previously described from Brazil and provided more information on naturalized taxa. Overall, we expanded the confirmed number of native Brazilian Selaginella species to 91 and confirmed six introduced and naturalized taxa in the country. Conclusions: The description of S. pectopuellensis adds to our knowledge of Brazil's pteridophyte flora. We synonymized S. kriegeriana under S. magnafornensis and clarified that S. bahiensis subsp. bahiensis and S. bahiensis subsp. manausensis should not be recognized as separate taxa. We also confirmed six naturalized Selaginella taxa in Brazil

Nanoparticle-Mediated Genetic Transformation in a Selaginella Species.

The genus Selaginella holds a key phylogenetic position as a sister species to vascular plants, encompassing desiccation-tolerant members. Some Selaginella species thrive in extremely arid conditions, enduring significant water loss and recovering upon rehydration. Consequently, Selaginella has emerged as a model system for studying desiccation tolerance in plant science. However, the absence of an efficient genetic transformation system has limited the utility of Selaginella species as a model. To address this constraint, we developed a nanoparticle-mediated transformation tool utilizing arginine-functionalized nanohydroxyapatites. This biocompatible system enabled the transient expression of the GFP, GUS, and eYGFPuv reporter genes in Selaginella moellendorffii. Establishing a stable genetic transformation technique for S. moellendorffii holds promise for application to other Selaginella species. This tool could be instrumental in identifying genetic resources for crop improvement and understanding genome-level regulatory mechanisms governing desiccation tolerance in Selaginella species. Furthermore, this tool might aid in identifying key regulatory genes associated with desiccation tolerance, offering potential applications in enhancing drought-sensitive crops and ensuring sustainable food production.

Two New Species of Selaginella from India

No Abstract.

Epidermal Studies in the Genus <i>Selaginella</i> Beauv.

Epidermal studies of thirty seven Indian species of Selaginella have been carried out. On the basis of the presence or absence of sclerotic fibres on the margin of the leaves, distribution of stomata and presence or absence of a ring of subsidiary cells around the stoma etc., a tentative key for the identification of these heterophyllous Indian species of Selaginella has been devised.

Structure of the ligule in American species of Selaginella P. Beauv. (Selaginellaceae)

The ligule is an important character in the taxonomic delimitation of Selaginella species. Here, the morphology of this organ is described in 11 American species. Four of these species are xerophytic: Selaginella convoluta, S. microphylla, S. peruviana, and S. sellowii, and seven are mesophytic: S. anceps, S. diffusa, S. flagellata, S. flexuosa, S. mollis, S. silvestris, and S. sulcata. Morphological data were obtained by traditional histological techniques. Observations were made by light and scanning electron microscopy. Variations in ligule size in vegetative leaves and sporophylls were determined using a correlation analysis with Spearman's coefficient. The ligule was found to have five body shapes: campanulate, linguiform, elliptic, fan-shaped, and rectangular. Each shape can have a lobed (bi-, tri-, or multi-lobed), rounded, or truncate apex. Size, shape, and apex are characteristic of each species and remain constant in young and mature leaves. No significant differences were observed between xerophytic and mesophytic species. The ligule of all species studied is described for the first time. Micrographs of all the species studied are presented, and the morphological results of this study have been mapped into the recent phylogeny of the genus.

Taxonomic significance of megaspores in some species of Selaginella from Arunachal Pradesh in India.

The present study was carried out to record the color, size, and ornamentation of megaspores in 18 species of the family Selaginellaceae from Arunachal Pradesh using scanning electron microscope (SEM) and light microscope (LM). Electron microscopic study of the spore features revealed the type of ornamentation and microsculptural detail. SEM study on megaspore of Selaginella pentagona (S. pentagona), Selaginella tenuifolia, Selaginella semicordata, and Selaginella chrysorrhizos is presented for the first time. Variation in the megaspore ornamentation is noted at the interspecific level and intraspecific level in some cases. Examination of the megaspores under study found all the megaspores as trilete, with a size ranging from 116 to 560 μm in diameter. Taxonomic key is prepared to differentiate the species. Short descriptions of megaspores are provided and supported by photo plates. New features are recorded for seven species. The study contributes to the separation of species within the genus Selaginella based on the spore feature and brings forward the use of spore as a diagnostic tool in the taxonomy of the genus. These works contribute to the systematic of the family Selaginellaceae and provide useful information in the field of palynology. RESEARCH HIGHLIGHTS: Study on megaspore features of Selaginella species collected from Arunachal Pradesh, using SEM and LM. Taxonomic key is provided for each species based on megaspores features. New megaspore features are recorded for the seven species. The study brings forward the use of spore as a diagnostic tool in the taxonomy of the genus. These works provide useful information in the field of systematic and palynology.

A study on molecular taxonomy of South Indian species Selaginella sweared by DNA barcoding using rbcL

In this study, genetic polymorphisms using DNA barcoding has been performed on selected ten species of Selaginella collected form Tamil Nadu and the Hills of Kerala. The main aim of this study was to estimate a phylogenetic and evolutionary relationship between selected species of Selaginella using DNA barcoding. The genomic DNA of selected species of Selaginella was isolated and were examined for DNA polymorphisms. The method described by Sanger has been used to sequence the PCR rbcL products. The phylogenetic analysis was carried out using four methods viz., minimum evolution, neighbor joining, UPGMA and maximum parsimony. For the studied species, the PCR amplification result was good, the molecular weight range from 500 to 600 base pairs and the amplicons were sequenced. The obtained sequences were aligned, annotated and submitted in GenBank. The phylogenetic analysis of studied Selaginella species using minimum evolution, NJ and UPGMA methods showed similar trees whether maximum parsimony tree displayed varied tree. The sequence alignment results illustrated that the sequence of S. involvens, S. intermedia, S. inaequalifolia, S. wightii and S. tenera were distinct from the other studied Selaginella species viz., S. brachystachya, S. repanda, S. radicata, S. bryopteris and S. delicatula. The cladistics tree also explains the relationship between S. delicatula with and without cones. This concludes that rbcL data is most valuable for inferring phylogenetic relationship between closely related species. DNA barcoding using rbcL gene was applied to distinguish the inter-specific variation among the selected Selaginella species.

Desiccation tolerance mechanisms of resurrection plant Selaginella pulvinata

The resurrection plant Selaginella pulvinata possesses an extraordinary ability to survive longterm desiccation, with the capacity to recover to normal growth after four years in a desiccated state. To understand the phenomenon, we investigated morphology, cytology, physiology, and performed PacBio single-molecule, real-time (SMRT) sequencing and Illumina RNA-sequencing of S. pulvinata during dehydration and rehydration. The full-length transcriptome dataset of S. puvinata consisted of 78,914 isoforms, and 75,819 isoforms (96.07%) were functionally annotated. The mapping rate of RNA-seq was 86.83–93.46% when utilizing the full-length transcriptome dataset as a reference. A total of 17,934 differentially expressed genes (DEGs) were identified during dehydration and rehydration. During dehydration, swollen chloroplasts and mitochondria, as well as vacuolation occupied space in desiccated cells, which cooperated with dense cytoplasm to inhibit the collapse and folding of desiccated cells. Accumulation and up-regulated gene expressions of osmotic agent and protective proteins contributed to the formation of vacuolation and dense cytoplasm. To reduce ROS damage during dehydration, two strategies were employed in S. pulvinata, i.e., reducing ROS production and scavenging ROS. Reducing exposure area, inactive PSII and down-regulated gene expression in photosynthesis decreased ROS production caused by excessive light absorption. Increased activities and up-regulated gene expressions in antioxidant enzyme system promoted ROS scavenging. ABA signaling pathway was hypothesized to play an important regulatory role in the desiccation tolerance of S. pulvinata due to significant ABA accumulation and up-regulated expressions of related genes during dehydration. Moreover, the comparative transcriptome analysis revealed that the pathways involved in dehydration and rehydration of the resurrection species S. pulvinata, S. lepidophylla and S. sellowii were consistent, indicating the similar desiccation tolerance mechanisms existing in the different resurrection species of Selaginella. Our study preliminarily revealed the desiccation tolerance mechanisms of S. pulvinata, which holds significant potential for inspiring biotechnological strategies aimed at enhancing drought tolerance in crops.

Sporangial arrangement patterns in Selaginella strobili of Arunachal Pradesh, a state in North East India: An insightful analysis

The study on sporangial arrangement patterns in strobili of Selaginella species from Arunachal Pradesh, India aims to provide a morphological analysis of strobili in 20 species of Selaginella. The study recorded variations in the distributional patterns of sporangia in the strobili within and among the Selaginella species. It provides a detailed description of the position and features of strobili, the number and position of microsporangia and megasporangia per strobili, the shape, size and margin of sporophylls and the number of megaspores per megasporangium which are useful in taxonomic delimitation. We provided photo plates of strobili in 20 species of the genus, 16 patterns of sporangial arrangement and a table which includes sampling details along with statistical analysis based on the size of strobili and sporophylls.

Ultrastructural organization of the thylakoid system during the afternoon relocation of the giant chloroplast in Selaginella martensii Spring (Lycopodiophyta)

Within the ancient vascular plant lineage known as lycophytes, many Selaginella species contain only one giant chloroplast in the upper epidermal cells of the leaf. In deep-shade species, such as S. martensii, the chloroplast is cup-shaped and the thylakoid system differentiates into an upper lamellar region and a lower granal region (bizonoplast). In this report, we describe the ultrastructural changes occurring in the giant chloroplast hosted in the epidermal cells of S. martensii during the daily relocation of the organelle. The process occurs in up to ca. 40% of the microphylls without the plants being exposed to high-light flecks. The relocated chloroplast loses its cup shape: first, it flattens laterally toward the radial cell wall and then assumes a more globular shape. The loss of the conical cell shape, the side-by-side lateral positioning of vacuole and chloroplast, and the extensive rearrangement of the thylakoid system to only granal cooperate in limiting light absorption. While the cup-shaped chloroplast emphasizes the light-harvesting capacity in the morning, the relocated chloroplast is suggested to support the renewal of the thylakoid system during the afternoon, including the recovery of photosystem II (PSII) from photoinhibition. The giant chloroplast repositioning is part of a complex reversible reshaping of the whole epidermal cell.

Selaginella likabalika Aran & Roy sp. nov: a new species from Arunachal Pradesh, India

A new species of Selaginella i.e., Selaginella likabalika is described in the present study. The species was collected from Likabali, under the Lower Siang district and Karsingsa, under the Papumpare district of Arunachal Pradesh. The new species can be easily confused to be mosses due to their similar appearance and habitat resemblance. The species is minute, prostrate and generally covers the ground like a carpet. The morphology of the new species is close to Selaginella armata, S. apoda, S. confusa and S. flacca but can be differentiated by leaf features.

Advances in the Anti-Tumor Activity of Biflavonoids in Selaginella.

Despite the many strategies employed to slow the spread of cancer, the development of new anti-tumor drugs and the minimization of side effects have been major research hotspots in the anti-tumor field. Natural drugs are a huge treasure trove of drug development, and they have been widely used in the clinic as anti-tumor drugs. Selaginella species in the family Selaginellaceae are widely distributed worldwide, and they have been well-documented in clinical practice for the prevention and treatment of cancer. Biflavonoids are the main active ingredients in Selaginella, and they have good biological and anti-tumor activities, which warrant extensive research. The promise of biflavonoids from Selaginella (SFB) in the field of cancer therapy is being realized thanks to new research that offers insights into the multi-targeting therapeutic mechanisms and key signaling pathways. The pharmacological effects of SFB against various cancers in vitro and in vivo are reviewed in this review. In addition, the types and characteristics of biflavonoid structures are described in detail; we also provide a brief summary of the efforts to develop drug delivery systems or combinations to enhance the bioavailability of SFB monomers. In conclusion, SFB species have great potential to be developed as adjuvant or even primary therapeutic agents for cancer, with promising applications.

(2943) Proposal to conserve Selaginella, nom. cons., (Selaginellaceae) with a conserved type

(2943) Proposal to conserve <i>Selaginella</i>, nom. cons., (<i>Selaginellaceae</i>) with a conserved type

Selaginella P.Beauv. (Selaginellaceae) no estado do Maranhão, nordeste, Brasil: Levantamento florístico e novo registro para o domínio Cerrado

Abstract This work is a floristic study of Selaginella in Maranhão. The species survey is based on collections from fieldwork conducted between April 2006 and February 2023 and specimens from Maranhão deposited at the CCAA, HBRA, MG, and SLUI herbaria. Ten species were identified: Selaginella conduplicata, S. convoluta, S. erythropus, S. flagellata, S. gynostachya S. marginata, S. minima, S. radiata, S. simplex, and S. sulcata. We report the first record of S. gynostachya for Maranhão and the Cerrado domain in Brazil. Until now, this species was only known from areas of Amazonia. We provide a map with records, an identification key, and comments about the identification and geographic distribution of Selaginella species in Maranhão state. For the new record, we also provide photos.

Methyl jasmonate induces selaginellin accumulation in Selaginella convoluta.

Selaginellins are specialized metabolites and chemotaxonomic markers for Selaginella species. Despite the growing interest in these compounds as a result of their bioactivities, they are accumulated at low levels in the plant. Hence, their isolation and chemical characterization are often difficult, time consuming, and limiting for biological tests. Elicitation with the phytohormone methyl jasmonate (MeJA) could be a strategy to increase the content of selaginellins addressing their low availability problem, that also impairs pharmacological investigations. In this study, we examined MeJA elicitation in Selaginella convoluta plants, a medicinal plant found in northeastern Brazil, by treating them with two different concentrations (MeJA: 50 and 100µM), followed by chemical profiling after 12, 24 and 48h after application. Samples were harvested and analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). MeJA treatment significantly impacted the chemical phenotype. Regarding shoots differences in the time-dependent increased accumulation of all metabolites when plants were subjected to 100µM MeJA were observed while in roots, most metabolites had their concentrations decreased in a time-dependent fashion at the same conditions. Results support organ, MeJA concentration and time post-treatment dependence of specialized metabolite accumulation, mainly the flavonoids and selaginellins. The amount of Selaginellin G in shoots of MeJA-treated specimens increased in 5.63-fold relative to control. The molecular networking approach allowed for the putative annotation of 64 metabolites, among them, the MeJA treatment followed by targeted metabolome analysis also allowed to annotate seven unprecedented selaginellins. Additionally, the in silico bioactive potential of the annotated selaginellins highlighted targets related to neurodegenerative disorders, antiproliferative, and antiparasitic issues. Taken together, data point out MeJA exposure as a strategy to induce potentially bioactive selaginellins accumulation in S. convoluta, this approach could enable a deep investigation about the metabolic function of these metabolites in the genus as well as regarding pharmacological exploration of the undervalued potential.

Mitogenome-based phylogenomics provides insights into the positions of the enigmatic sinensis group and the sanguinolenta group in Selaginellaceae (Lycophyte)

Spikemoss (Selaginellaceae) is one of the basal lineages of vascular plants. This family has a single genus Selaginella which consists of about 750 extant species. The phylogeny of Selaginellaceae has been extensively studied mainly based on plastid DNA and a few nuclear sequences. However, the placement of the enigmatic sinensis group is a long-term controversy because of the long branch in the plastid DNA phylogeny. The sanguinolenta group is also a phylogenetically problematic clade owing to two alternative positions resulted from different datasets. Here, we newly sequenced 34 mitochondrial genomes (mitogenomes) of individuals representing all seven subgenera and major clades in Selaginellaceae. We assembled the draft mitogenomes and annotated the genes and performed phylogenetic analyses based on the shared 17 mitochondrial genes. Our major results include: (1) all the assembled mitogenomes have complicated structures, unparalleled high GC content and a small gene content set, and the positive correlations among GC content, substitution rates and the number of RNA editing sites hold; (2) the sinensis group was well supported as a member of subg. Stachygynandrum; (3) the sanguinolenta group was strongly resolved as sister to all other Selaginella species except for subg. Selaginella. This study demonstrates the potential of mitogenome data in providing novel insights into phylogenetically recalcitrant problems.

Taxonomic significance of microspore in some selected species of the family Selaginellaceae from Arunachal Pradesh, India.

Microspore morphology of 18 species of Selaginellaceae found in Arunachal Pradesh, North East India, is studied using light microscope and electron microscope. Of the eighteen taxa studied, study on five taxa is attempted for the first time using electron microscope. The species studied exhibit variation in size, shape, color and ornamentation of the microspore. The measurement of equatorial diameter ranges from 11–57 µm. Tetrad form of the microspore is recorded in four species. The variations in the microspore ornamentation within the species of the family are useful in identification, classification and taxonomic distinction of the species. Identification key is provided for the species under study. This study is beneficial for the enumeration of basic information of microspores of the family and for the precise identification of Selaginella species. Statistical analysis in distal and proximal surface ornamentation of the microspores is provided.

Foliar morphology and epidermal ultrastructure of four Selaginella species (Selaginellaceae – Lycophyta)

ABSTRACT The leaf morphology of Selaginella species from subtropical South America show differences in structure and ultrastructure that are useful for species identification. We studied the following epidermal traits: micromorphology of stomatal types, distribution patterns of silica cells, silica cells and silica bodies of Selaginella convoluta, S. microphylla, S. sellowii and S. sulcata, using light and scanning electron microscopy. Five stomatal types were observed, anomocytic, actinocytic, anisocytic, staurocytic and tetracytic and two additional variants, anomodiacytic and anomoparacytic. Five silica cell distribution patterns were identified, laminar, medial, medial-basiscopic, subcostal, and submarginal. Pyramidal silica bodies and conical bodies with concave base are described for the first time. In the studied species, silica bodies are pyramidal in S. convoluta and globular, conical and pyramidal in S. microphylla, whereas in S. sellowii and S. sulcata they are conical, with concave base of different sizes. Illustrations of the epidermal features, LM photographs, SEM micrographs and comparative tables are presented.

The evolution of extremely diverged plastomes in Selaginellaceae (lycophyte) is driven by repeat patterns and the underlying DNA maintenance machinery.

Two factors are proposed to account for the unusual features of organellar genomes: the disruptions of organelle-targeted DNA replication, repair, and recombination (DNA-RRR) systems in the nuclear genome and repetitive elements in organellar genomes. Little is known about how these factors affect organellar genome evolution. The deep-branching vascular plant family Selaginellaceae is known to have a deficient DNA-RRR system and convergently evolved organellar genomes. However, we found that the plastid genome (plastome) of Selaginella sinensis has extremely accelerated substitution rates, a low GC content, pervasive repeat elements, a dynamic network structure, and it lacks direct or inverted repeats. Unexpectedly, its organelle DNA-RRR system is short of a plastid-targeted Recombinase A1 (RecA1) and a mitochondrion-targeted RecA3, in line with other explored Selaginella species. The plastome contains a large collection of short- and medium-sized repeats. Given the absence of RecA1 surveillance, we propose that these repeats trigger illegitimate recombination, accelerated mutation rates, and structural instability. The correlations between repeat quantity and architectural complexity in the Selaginella plastomes support these conclusions. We, therefore, hypothesize that the interplay of the deficient DNA-RRR system and the high repeat content has led to the extraordinary divergence of the S. sinensis plastome. Our study not only sheds new light on the mechanism of plastome divergence by emphasizing the power of cytonuclear integration, but it also reconciles the longstanding contradiction on the effects of DNA-RRR system disruption on genome structure evolution.