Asterias Amurensis Research Articles

Immune Enhancement Effect of Asterias amurensis Fatty Acids through NF-κB and MAPK Pathways on RAW 264.7 Cells.

Asterias amurensis is a marine organism that causes damage to the fishing industry worldwide; however, it has been considered a promising source of functional components. The present study aimed to investigate the immune-enhancing effects of fatty acids from three organs of A. amurensis on murine macrophages (RAW 264.7 cells). A. amurensis fatty acids boosted production of immune-associated factors such as nitric oxide (NO) and prostaglandin E2 in RAW 264.7 cells. A. amurensis fatty acids also enhanced the expression of critical immune-associated genes, including iNOS, TNF-α, IL-1β, and IL-6, as well as COX-2. Western blotting showed that A. amurensis fatty acids stimulated the NF-κB and MAPK pathways by phosphorylation of NF-κB p-65, p38, ERK1/2, and JNK. A. amurensis fatty acids from different tissues resulted in different levels of NF-κB and MAPK phosphorylation in RAW 264.7 cells. The results increase our understanding of how A. amurensis fatty acids boost immunity in a physiological system, as a potential functional material.

The invasion risk of species associated with Japanese Tsunami Marine Debris in Pacific North America and Hawaii

Marine debris from the Great Tsunami of 2011 represents a unique transport vector for Japanese species to reach Pacific North America and Hawaii. Here we characterize the invasion risk of invertebrate species associated with tsunami debris using a screening-level risk assessment tool – the Canadian Marine Invasive Screening Tool (CMIST). Higher-risk invertebrate invaders were identified for each of five different ecoregions. Some of these are well-known global invaders, such as the mussel Mytilus galloprovincialis and the ascidian Didemnum vexillum which already have invasion histories in some of the assessed ecoregions, while others like the sea star Asterias amurensis and the shore crab Hemigrapsus sanguineus have yet to invade large portions of the assessed ecoregions but also are recognized global invaders. In general, the probability of invasion was lower for the Gulf of Alaska and Hawaii, in part due to lower climate matches and the availability of other invasion vectors.

A dynamic energy budget model to describe the reproduction and growth of invasive starfish Asterias amurensis in southeast Australia

The introduction of alien species is a global phenomenon that alters ecosystems structure and functioning. Invasive species are responsible for substantial economic and ecological losses. Invasive species impact resource availability, outcompeting and even causing extinction of native species. The management of invasive species requires knowledge on the ecology, physiology and population dynamics of these species. In a world where environmental conditions are changing fast due to global climate change and other anthropogenic stressors, a more comprehensive knowledge of the life history and physiology of these species is urgently needed. The DEB theory is unique in capturing the metabolic processes of an organism through its entire life cycle, and thus, is a useful tool to model lifetime feeding, growth, reproduction, and responses to changes in biotic and abiotic conditions. In this work, we estimated the parameters of a DEB model for Asterias amurensis. This starfish was introduced in Tasmania and is considered the most serious marine pest in Australia where it has caused local extinctions of several species. Asterias amurensis is a major predator and is a keystone species exerting top-down control of its prey populations by achieving large densities. We determined the influence of biotic and abiotic factors on the performance of A. amurensis. The DEB model presented here includes energy handling rules to describe gonad and pyloric caeca cycles. Model parameters were used to explore population dynamics of populations of A. amurensis in Australia. The DEB model allowed us to characterise the ecophysiology of A. amurensis, providing new insights on the role of food availability and temperature on its life cycle and reproduction strategy. Moreover it is a powerful tool for risk management of already established invasive populations and of regions with a high invasion risk.

Tracking the Northern Pacific sea star Asterias amurensis with acoustic transmitters in the scallop mariculture field of Hokkaido, Japan

The Northern Pacific sea star Asterias amurensis has a major negative impact on scallop mariculture. In northern Japan, fishermen clean up sea stars before releasing young scallops in the mariculture field; however, new sea stars constantly invade the field from outside areas to feed on scallops. Thus, it is important to determine the migration speed and seasonal behavioral patterns of the Northern Pacific sea star to implement effective density control measures. Here, we set out to quantify these parameters using acoustic telemetry. In a rearing experiment, acoustic transmitters were retained on sea stars for up to 71 days using nylon fishing line. In the field experiment, we showed that the moving distance of the Northern Pacific sea star over a 1-week period was significantly further in spring (90.9 ± 49.9 m) than in summer (25.1 ± 18.9 m), and that the moving speed was significantly faster in spring (18.1 ± 15.2 m/day) than in summer (4.3 ± 9.1 m/day). Our results are the first to present the two-dimensional movement of Northern Pacific sea star individuals in spring and summer. We suggest that sea star extermination practices should be extended beyond the immediate culture area.

Multiparametric comparative analysis of coelomocytes in Asterias amurensis and Lysastrosoma anthosticta

Behavioral dynamics of coelomocytes from echinoderms Asterias amurensis and Lysastrosoma anthosticta during the first hour of in vitro cultivation was analyzed using a wide range of linear and fractal parameters of the external morphology. Most of the parameters, including values of the cell bounding circle and convex hull, asymmetry, fractal dimensions of contour images, lacunarity, and cell density and area, showed species-specific behavior of the immune cells of the studied animals. The cells differed in a wide range of parameters as early as two min after seeding on the substrate. The cells acquired the largest morphological differences by the fifth min of cultivation. Both cell dynamics in general and analysis of the cell morphology at individual points in time may serve as markers for species-specificity of cells. However, when morphology is compared at one point in time, at least two parameters associated with significant morphological differences in cells of the studied species should be used because of overlapping tendencies in changes in morphological features.

Enzyme-linked immunosorbent assay of relaxin-like gonad-stimulating peptide in the starfish Patiria (Asterina) pectinifera

A relaxin-like gonad-stimulating peptide (RGP) from starfish Patiria (Asterina) pectinifera is the first identified invertebrate gonadotropin for final gamete maturation. Recently, we succeeded in obtaining specific antibodies against P. pectinifera RGP (PpeRGP). In this study, the antibodies were used for the development of a specific and sensitive enzyme-linked immunosorbent assay (ELISA) for the measurement of PpeRGP. A biotin-conjugated peptide that binds to peroxidase-conjugated streptavidin is specifically detectable using 3,3′,5,5′-tetramethylbenzidine (TMB)/hydrogen peroxide as a substrate; therefore, biotin-conjugated RGP (biotin-PpeRGP) was synthesized chemically. Similarly to PpeRGP, synthetic biotin-PpeRGP bound to the antibody against PpeRGP. In binding experiments with biotin-PpeRGP using wells coated with the antibody, a displacement curve was obtained using serial concentrations of PpeRGP. The ELISA system showed that PpeRGP could be measured in the range 0.01–10pmol per 50µl assay buffer. On the contrary, the B-chains of PpeRGP, Asterias amurensis RGP, Aphelasterias japonica RGP, and human relaxin showed minimal cross-reactivity in the ELISA, except that the A-chain of PpeRGP affected it slightly. These results strongly suggest that this ELISA system is highly specific and sensitive with respect to PpeRGP.

Microbiota in the coelomic fluid of two common coastal starfish species and characterization of an abundant Helicobacter-related taxon

Marine invertebrates associate with diverse microorganisms. Microorganisms even inhabit coelomic fluid (CF), namely, the fluid filling the main body cavity of echinoderms. The CF microbiota potentially impacts host health and disease. Here, we analysed the CF microbiota in two common coastal starfish species, Patiria pectinifera and Asterias amurensis. Although microbial community structures were highly variable among individual starfish, those of P. pectinifera were compositionally similar to those in the surrounding seawater. By contrast, many A. amurensis individuals harboured unique microbes in the CF, which was dominated by the unclassified Thiotrichales or previously unknown Helicobacter-related taxon. In some individuals, the Helicobacter-related taxon was the most abundant genus-level taxon, accounting for up to 97.3% of reads obtained from the CF microbial community. Fluorescence in situ hybridization using a Helicobacter-related-taxon-specific probe suggested that probe-reactive cells in A. amurensis were spiral-shaped, morphologically similar to known Helicobacter species. Electron microscopy revealed that the spiral cells had a prosthecate-like polar appendage that has never been reported in Helicobacter species. Although culture of Helicobacter-related taxon was unsuccessful, this is the first report of the dominance of a Helicobacter-related taxon in invertebrates and non-digestive organs, reshaping our knowledge of the phylogeography of Helicobacter-related taxa.

Protein kinase A activity leads to the extension of the acrosomal process in starfish sperm

Acrosomal vesicles (AVs) of sperm undergo exocytosis during the acrosome reaction, which is immediately followed by the actin polymerization-dependent extension of an acrosomal process (AP) in echinoderm sperm. In the starfish Asterias amurensis, a large proteoglycan, acrosome reaction-inducing substance (ARIS), together with asteroidal sperm-activating peptide (asterosap) and/or cofactor for ARIS, induces the acrosome reaction. Asterosap induces a transient elevation of intracellular cGMP and Ca2+ levels, and, together with ARIS, causes a sustained increase in intracellular cAMP and Ca2+ . Yet, the contribution of signaling molecules downstream of cAMP and Ca2+ in inducing AV exocytosis and AP extension remain unknown. A modified acrosome reaction assay was used here to differentiate between AV exocytosis and AP extension in starfish sperm, leading to the discovery that Protein kinase A (PKA) inhibitors block AP extension but not AV exocytosis. Additionally, PKA-mediated phosphorylation of target proteins occurs, and these substrates localize at the base of the AP, demonstrating that PKA activation regulates an AP extension step during the acrosome reaction. The major PKA substrate was further identified, from A. amurensis and Asterias forbesi sperm, as a novel protein containing six PKA phosphorylation motifs. This protein, referred to as PKAS1, likely plays a key role in AP actin polymerization during the acrosome reaction.

Potential for biocontrol of the exotic starfish, Asterias amurensis, using a native starfish

Asterias amurensis is a starfish native to the northern Pacific that was introduced into southern Australia in the 1980s. It is widely viewed as one of Australia’s most serious invasive marine pests, but there are few methods available to control new or established populations. The role of Coscinasterias muricata in controlling the distribution of Asterias in Port Phillip Bay, and its potential to eliminate new infestations of Asterias were investigated. Laboratory feeding trials, where alternative mussel prey were available, showed Coscinasterias consumed Asterias at the rate of ~45/year. Field surveys in Port Phillip Bay showed that most Coscinasterias occurred at depths shallower than 15 m, while most Asterias occurred at depths greater than 15 m, and the ratio of Asterias/Coscinasterias only exceeded 45 at depths greater than 15 m. Consequently, if laboratory and field feeding rates are similar, Coscinasterias would be expected to exert significant control over Asterias populations at depths shallower than 15 m, and augmenting Coscinasterias populations at sites of new Asterias infestations may help eliminate newly-established populations.

English

The starfish Asterias amurensis is one of the common species in Japanese coastal area. The species is considered an extremely rich source of biological active compounds, including saponin. Saponins are secondary metabolites and exhibit a wide spectrum of biological activities. The species of starfish caught in Kobe, Hyogo prefecture, Japan, was analyzed for species identification and micronutrient content. The starfish extract was evaluated for different biological properties and its fractions obtained using thin layer chromatography (TLC). Nucleotide sequence analysis of the 16S rRNA gene fragment of mitochondrial DNA indicated that partial sequences of PCR products of the species was identical with that of A. amurensis. The micronutrient contents results showed that nitrogen (N) content of the starfish was 1.50% of dry weight and the copper content was 2.10 µg/g. The crude extract of A. amurensis exhibited predominant growth inhibitory activity against six human fungal pathogens and also showed hemolytic activity against 2% sheep erythrocyte. The present findings suggest the possible pharmacological applications of A. amurensis that can be used as food ingredients and antifungal component. Key words: Asterias amurensis, crude extract, biological property, saponin, antifungal component.

Radioimmunoassay of relaxin-like gonad-stimulating peptide in the starfish Patiria (=Asterina) pectinifera

A relaxin-like gonad-stimulating peptide (RGP) from starfish Patiria (=Asterina) pectinifera is the first identified invertebrate gonadotropin for final gamete maturation. An antiserum against P. pectinifera RGP (PpeRGP) was produced by immunizing rabbits with a PpeRGP sulfanyl-polyethylene glycol derivative conjugated with keyhole limpet hemocyanin (KLH) as the antigen. The antiserum was used for the development of a specific and sensitive radioimmunoassay (RIA) for the measurement of RGP. In binding experiments using radioiodinated PpeRGP and antiserum against PpeRGP, a displacement curve was obtained using radioinert PpeRGP. The sensitivity of the RIA, defined as the amount of PpeRGP that significantly decreased the counts by 2 SD from the 100% bound point, averaged 0.040±0.002pmol PpeRGP per 100μl assay buffer (0.40±0.02nM) in 10 assays. Intra-assay and inter-assay coefficients of variation were 6.1% and 2.7%, respectively. Serial dilution of whole homogenates from the radial nerve cords and circumoral nerve-rings of P. pectinifera produced displacement curves parallel to the PpeRGP standard. Thus, the amounts of PpeRGP were determined as 1.54±0.09pmol/mg wet weight of radial nerves and 0.87±0.04pmol/mg wet weight of nerve-rings, respectively. On contrary, pyloric stomach, pyloric caeca, tube-feet, ovaries, testes, and ovarian follicle cells did not react in the RIA system. Furthermore, the A- and B-chains of PpeRGP, Asterias amurensis RGP, bovine insulin, and human relaxin did not show cross-reactivity in the RIA. These results strongly suggest that the RIA system is a highly specific and sensitive with respect to PpeRGP.

Multiple dispersal vectors drive range expansion in an invasive marine species.

The establishment and subsequent spread of invasive species is widely recognized as one of the most threatening processes contributing to global biodiversity loss. This is especially true for marine and estuarine ecosystems, which have experienced significant increases in the number of invasive species with the increase in global maritime trade. Understanding the rate and mechanisms of range expansion is therefore of significant interest to ecologists and conservation managers alike. Using a combination of population genetic surveys, environmental DNA (eDNA) plankton sampling and hydrodynamic modelling, we examined the patterns of introduction of the predatory Northern Pacific seastar (Asterias amurensis) and pathways of secondary spread within southeast Australia. Genetic surveys across the invasive range reveal some genetic divergence between the two main invasive regions and no evidence of ongoing gene flow, a pattern that is consistent with the establishment of the second invasive region via a human-mediated translocation event. In contrast, hydrodynamic modelling combined with eDNA plankton sampling demonstrated that the establishment of range expansion populations within a region is consistent with natural larval dispersal and recruitment. Our results suggest that both anthropogenic and natural dispersal vectors have played an important role in the range expansion of this species in Australia. The multiple modes of spread combined with high levels of fecundity and a long larval duration in A.amurensis suggests it is likely to continue its range expansion and significantly impact Australian marine ecosystems.

Molecular Genetic Markers of Intra- and Interspecific Divergence within Starfish and Sea Urchins (Echinodermata).

A fragment of the mitochondrial COI gene from isolates of several echinoderm species was sequenced. The isolates were from three species of starfish from the Asteriidae family (Asterias amurensis and Aphelasterias japonica collected in the Sea of Japan and Asterias rubens collected in the White Sea) and from the sea urchin Echinocardium cordatum (family Loveniidae) collected in the Sea of Japan. Additionally, regions including internal transcribed spacers and 5.8S rRNA (ITS1 - 5.8S rDNA - ITS2) were sequenced for the three studied starfish species. Phylogenetic analysis of the obtained COI sequences together with earlier determined homologous COI sequences from Ast. forbesii, Ast. rubens, and Echinocardium laevigaster from the North Atlantic and E. cordatum from the Yellow and North Seas (GenBank) placed them into strictly conspecific clusters with high bootstrap support (99% in all cases). Only two exceptions- Ast. rubens DQ077915 sequence placed with the Ast. forbesii cluster and Aph. japonica DQ992560 sequence placed with the Ast. amurensis cluster- were likely results of species misidentification. The intraspecific polymorphism for the COI gene within the Asteriidae family varied within a range of 0.2-0.9% as estimated from the genetic distances. The corresponding intrageneric and intergeneric values were 10.4-12.1 and 21.8-29.8%, respectively. The interspecific divergence for the COI gene in the sea urchin of Echinocardium genus (family Loveniidae) was significantly higher (17.1-17.7%) than in the starfish, while intergeneric divergence (14.6-25.7%) was similar to that in asteroids. The interspecific genetic distances for the nuclear transcribed sequences (ITS1 - 5.8S rDNA - ITS2) within the Asteriidae family were lower (3.1-4.5%), and the intergeneric distances were significantly higher (32.8-35.0%), compared to the corresponding distances for the COI gene. These results suggest that the investigated molecular-genetic markers could be used for segregation and identification of echinoderm species.

Novel pentapeptide, PALAL, derived from a bony fish elicits contraction of the muscle in starfish Patiria pectinifera.

A bioactive peptide mimicking peptide-signaling molecules has been isolated from the skin extract of fish Channa argus which caused contraction of the apical muscle of a starfish Patiria pectinifera, a deuterostomian invertebrate. The primary structure of the isolated pentapeptide comprises amino acid sequence of H-Pro-Ala-Leu-Ala-Leu-OH (PALAL) with a molecular mass of 483.7 Da. Pharmacological activity of PALAL, dosage ranging from 10-9 to 10-5 M, revealed concentration-dependent contraction of the apical muscles of P. pectinifera and Asterias amurensis. However, PALAL was not active on the intestinal smooth muscle of the goldfish Carassius auratus and has presumably other physiological roles in fish skin. Investigation of structure-activity relationship using truncated and substituted analogs of PALAL demonstrated that H-Ala-Leu-Ala-Leu-OH was necessary and should be sufficient to constrict apical muscle of P. pectinifera. Furthermore, the second alanine residue was required to display the activity, and the fifth leucine residue was responsible for its potency. Comparison with PALAL's primary structure with those of other known bioactive peptides from fish and starfish revealed that PALAL does not have any significant homology. Consequently, PALAL is a bioactive peptide that elicits a muscle contraction in starfish, and the isolation of PALAL may lead to develop other bioactive peptides sharing its similar sequence and/or activity. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.

Influence of timing of fishing on trophic levels and diets of typical fish and invertebrate species in the Bohai Strait over a single year based on carbon and nitrogen isotope analysis

Fishing is the most widespread human exploitation of marine resources, which has an annual cyclical influence on aquatic species in Chinese offshore waters. This study used carbon and nitrogen isotopic ratios as tracers to reveal the changes in trophic level and dietary composition of offshore organisms during four cruises in March, June, August and November 2014. The results indicated that the trophic levels of fishes declined during two fishing periods, from March (average trophic level=3.36) to June (3.01), and from August (2.99) to November (2.57), while most invertebrates did not show this trend. The self-restoring ability of this ecosystem was reflected in the trophic level changes after the closed fishing season (from June 1 to September 1). The trophic levels of fishes remained stable, and some species even recovered such as Enchelyopus elongates (trophic level increased from 2.84 in June to 2.86 in August), Cryptocentrus filifer (from 3.10 to 3.12), and Ernogrammus hexagrammus (from 2.91 to 2.96). According to the trophic results, we selected the invertebrates Octopus minor and Asterias amurensis from the top trophic levels for dietary composition analysis. The composition of their diets changed significantly after fishing periods, and the proportions of some smaller and “non-commercial” species increased, such as Notoacmea schrenckii and Chlorostoma rustica. After the closed fishing season, the larger and “commercial” species contributed a greater proportion to their diet composition. These results indicated that the closed fishing season should be prolonged to give the ecosystem enough time to restore itself and further halt the trend of this fishery towards environment deterioration.

From pole to pole: the potential for the Arctic seastar Asterias amurensis to invade a warming Southern Ocean.

Due to climatic warming, Asterias amurensis, a keystone boreal predatory seastar that has established extensive invasive populations in southern Australia, is a potential high-risk invader of the sub-Antarctic and Antarctic. To assess the potential range expansion of A.amurensis to the Southern Ocean as it warms, we investigated the bioclimatic envelope of the adult and larval life stages. We analysed the distribution of adult A.amurensis with respect to present-day and future climate scenarios using habitat temperature data to construct species distribution models (SDMs). To integrate the physiological response of the dispersive phase, we determined the thermal envelope of larval development to assess their performance in present-day and future thermal regimes and the potential for success of A.amurensis in poleward latitudes. The SDM indicated that the thermal 'niche' of the adult stage correlates with a 0-17°C and 1-22.5°C range, in winter and summer, respectively. As the ocean warms, the range of A. amurensis in Australia will contract, while more southern latitudes will have conditions favourable for range expansion. Successful fertilization occurred from 3 to 23.8°C. By day 12, development to the early larval stage was successful from 5.5 to 18°C. Although embryos were able to reach the blastula stage at 2°C, they had arrested development and high mortality. The optimal thermal range for survival of pelagic stages was 3.5-19.2°C with a lower and upper critical limit of 2.6 and 20.3°C, respectively. Our data predict that A.amurensis faces demise in its current invasive range while more favourable conditions at higher latitudes would facilitate invasion of both larval and adult stages to the Southern Ocean. Our results show that vigilance is needed to reduce the risk that this ecologically important Arctic carnivore may invade the Southern Ocean and Antarctica.

The distribution of macrobenthic epifauna in the Far Eastern Marine Reserve based on remote underwater video data

The spatial distribution of epifauna in the Far Eastern Marine Reserve was examined using a remotely operated vehicle. The abundance and distribution patterns of the sea stars Patiria pectinifera, Distolasterias nipon, and Asterias amurensis, as well as those of brittle stars, the black sea cucumber Cucumaria japonica, the sea urchin Strongylocentrotus intermedius, the ascidian Halocynthia aurantium, hermit crabs, and the Japanese scallop Mizuhopecten yessoensis were determined in the South Section of the Reserve. The average biomass of five dominant epifaunal species ranged from 51.0 to 87.4% of the average biomass of the softbottom communities.

Ultrastructural evidence of the excretory function in the asteroid axial organ (Asteroidea, Echinodermata).

The ultrastructure of the axial organ of Asterias amurensis has been studied The organ is a network of canals of the axial coelom separated by haemocoelic spaces. The axial coelom is lined with two types of monociliary cells: podocytes and musculo-epithelial cells. Podocytes form numerous basal processes adjacent to the basal lamina on the coelomic side. Musculo-epithelial cells form processes running along the basal lamina. Some bundles of these processes wrapped in the basal lamina pass through haemocoelic spaces between neighboring coelomic canals. It is hypothesized that the axial organ serves for filtration of fluid from haemocoelic spaces into the axial coelom cavity, from which urine is excreted through the madreporite to the exterior.

A relaxin-like gonad-stimulating peptide from the starfish Aphelasterias japonica

Relaxin-like gonad-stimulating peptide (RGP) in starfish is the first identified invertebrate gonadotropin responsible for final gamete maturation. In this study, a new ortholog RGP was identified from Aphelasterias japonica. The DNA sequence encoding A. japonica RGP (AjaRGP) consists of 342 base pairs with an open reading frame encoding a peptide of 113 amino acids (aa), including a signal peptide (26aa), B-chain (20aa), C-peptide (42aa), and A-chain (25aa). AjaRGP is a heterodimeric peptide with disulfide cross-linkages. Comparing with Asterias amurensis RGP (AamRGP) and Patiria (=Asterina) pectinifera RGP (PpeRGP), the amino acid identity levels of AjaRGP with respect to AamRGP and PpeRGP are 84% and 58% for the A-chain and 90% and 68% for the B-chain, respectively. This suggests that AjaRGP is closer to AmaRGP rather than PpeRGP. Although chemical synthetic AjaRGP can induce gamete spawning and oocyte maturation in ovarian fragments of A. japonica, the ovary of P. pectinifera fails to respond to AjaRGP. This suggests that AjaRGP acts species-specifically.

The small cells of coelomic fluid and coelomic epithelium isolated from starfish Asterias rubens and Asterias amurensis (Echinodermata: Asteroidea): Comparative analysis of cell morphology and proliferative activity in vivo and in vitro

Earlier we revealed the probable candidates for the role of Asteroidea stem cells in the starfish Asterias rubens L., small coelomic epithelial cells (SECs-1) with a high nuclear–cytoplasmic ratio that were able to proliferate in vivo and in vitro. To check the existence of a similar cell type in other members of Asteroidea, the small cells in suspensions of coelomic fluid (CF) and coelomic epithelium (CE) of A. amurensis were analyzed with respect to their morphology and proportion in the total cell pool. The morphology of proliferating cells and the proliferative activity of CF and CE cells in vivo and in vitro were studied. The small cells with parameters identical to those of A. rubens SECs-1, were found both in CF and CE of related species. The subpopulation of weakly attached CE cells, highly enriched with SECs-1, was detected. These cells were able to migrate from CE and to proliferate in vivo and in vitro. Additionally, large proliferating cells were described in both starfish. The dynamics of proliferative activity in primary cell cultures of these starfish had some distinctions. Moreover, for the first time, the formation of “crystals”, the potential centres of spiculogenesis, was observed in primary culture of A. amurensis CE cells. The data prove that SECs may fulfil the common functions in two members of Asteroidea.