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PeerJ 2023Antennae in crayfish are essential for gaining information about the local topography and localising food, chemicals, conspecifics or predator. There are still gaps in...
BACKGROUND
Antennae in crayfish are essential for gaining information about the local topography and localising food, chemicals, conspecifics or predator. There are still gaps in the research on the morphology of antennae in decapods compared to other arthropods.
METHODOLOGY
Biometrical and ultrastructural methods were applied using light and cryo-scanning electron microscopies to study the morphology of antennae in six different crayfish species, including marbled crayfish , Mexican dwarf crayfish , red swamp crayfish , signal crayfish , common yabby , and spiny-cheek crayfish to find their potential morphological differences.
RESULTS
Significant differences in the antenna length, length and width of each segment to carapace length ratios, and the number of segments were found in the six crayfish species. The ultrastructure revealed differences in the distribution of sensory hairs on the antenna and the morphology of the antennal surface.
CONCLUSIONS
The different morphology of antennae might reflect adaptation to the conditions of their specific habitats. In addition, results showed that a combination of differences in the morphological features and biometrical measurements of antennae could be used for the distinguishment of different studied crayfish species.
Topics: Animals; Astacoidea; Ecosystem; Seafood; Hair
PubMed: 36908819
DOI: 10.7717/peerj.15006 -
Frontiers in Immunology 2022Gene duplication (GD) leads to the expansion of gene families that contributes organisms adapting to stress or environment and dealing with the infection of various...
Gene duplication (GD) leads to the expansion of gene families that contributes organisms adapting to stress or environment and dealing with the infection of various pathogens. C-type lectins (CTLs) in crustaceans undergo gene expansion and participate in various immune responses. However, the functions of different CTL produced by GD are not fully characterized. In the present study, two CTL genes (designated as and , respectively) were identified from . and originate from GD and the main difference between them is exon 3. PcLec-EPS and PcLec-QPS respectively contains EPS and QPS motif in their carbohydrate recognition domain. The mRNA levels of and in hemocytes, gills, intestine and lymph underwent time-dependent enhancement after D-Mannose and D-Galactose challenge. Recombinant PcLec-EPS and PcLec-QPS could bind to carbohydrates and microbes, and agglutinate bacteria. The results of experiments on recombinant protein injection and RNA interference indicate that PcLec-EPS and PcLec-QPS can respectively strong recognize and bind D-Mannose and D-Galactose, activate the Relish transcriptional factor, and further upregulate the expression of different antimicrobial peptides (AMPs). In addition, these two CTLs and Relish could positively regulate the expression of each other, suggesting that there is a positive feedback loop between two CTLs and Relish that regulates the expression of AMPs. It may contribute to the expansion of the immune response for host quickly and efficiently eliminating pathogenic microorganisms. This study provides new knowledge for clear understanding the significance and function of different CTL generated by GD in immune defenses in crustacean.
Topics: Animals; Astacoidea; Lectins, C-Type; Antimicrobial Peptides; Gene Duplication; Mannose; Galactose; Feedback
PubMed: 36353630
DOI: 10.3389/fimmu.2022.1021121 -
General and Comparative Endocrinology Sep 2020Insulin and related peptides play important roles in the regulation of growth and reproduction. Until recently three different types of insulin-related peptides had been...
Insulin and related peptides play important roles in the regulation of growth and reproduction. Until recently three different types of insulin-related peptides had been identified from decapod crustaceans. The identification of two novel insulin-related peptides from Sagmariasus verreauxi and Cherax quadricarinatus suggested that there might a fourth type. Publicly available short read archives show that orthologs of these peptides are commonly present in these animals. Most decapods have two genes coding such peptides, but Penaeus species have likely only one and some palaemonids have three. Interestingly, expression levels can vary more than thousand-fold in the gonads of Portunus trituberculatus, where gonadulin 1 is expressed by the testis and gonadulin 2 by the ovary. Although these peptides are also expressed in other tissues, the occasionally very high expression in the gonads led to them being called gonadulins.
Topics: Amino Acid Sequence; Animals; Astacoidea; Female; Gene Expression Regulation; Insulin; Male; Palinuridae; Phylogeny
PubMed: 32526328
DOI: 10.1016/j.ygcen.2020.113528 -
Journal of Invertebrate Pathology Jan 2022Iridovirids are a group icosahedral viruses containing linear double-stranded DNA, and mainly infect invertebrates and poikilothermic vertebrates. Cherax quadricarinatus...
Iridovirids are a group icosahedral viruses containing linear double-stranded DNA, and mainly infect invertebrates and poikilothermic vertebrates. Cherax quadricarinatus iridovirus (CQIV) is a new species of the family Iridoviridae and can cause high mortality in shrimps. In CQIV genome, there are 25 conserved genes and the putative products are involved in several viral processes. In this study, three core protein including CQIV-032R, CQIV-125R and CQIV-160L were identified to interact with CQIV-038R by yeast two-hybrid (Y2H), and the interaction between CQIV-038R and CQIV-125R was further confirmed by co-immunoprecipitation (Co-IP) assays. In the expression system, EGFP-038R and mCherry-125R were colocalized in the cytoplasm when co-expressed in Sf9 cells. Moreover, silencing the expression of 038R, 125R or both of these two proteins respectively in C. quadricarinatus cells by small interfering RNAs showed significantly inhibit CQIV replication. Collectively, we identified the interaction between 038R and 125R, and demonstrated they are essential for CQIV replication.
Topics: Animals; Astacoidea; Invertebrates; Iridoviridae; Iridovirus; Virus Replication
PubMed: 34838791
DOI: 10.1016/j.jip.2021.107699 -
Environmental Science and Pollution... Mar 2023Both physicochemical and biological factors affect the degree of metal accumulation in crayfish tissues. The content of metals and correlations between the metal...
Both physicochemical and biological factors affect the degree of metal accumulation in crayfish tissues. The content of metals and correlations between the metal concentrations in different tissues and the total length of crayfish is suitable indicators of contamination of the aquatic environment. The aim of the study was to analyse the effect of age and sex of crayfish on the degree of accumulation of Ca, Cu, and Zn in the muscle and exoskeleton. A total of 100 individuals of the spiny-cheek crayfish (Faxonius limosus, Rafinesque, 1817) were caught from Głowińsk reservoir (Poland) in October 2019 using fyke nets. Metal concentrations were determined in freeze-dried samples of the abdominal muscle, exoskeleton, bottom sediment, and water using atomic absorption spectroscopy (AAS). Here, we show that the highest concentrations of Zn were found in the muscle of 4-year-old females, Cu in 3-year-old males, and Ca in 4-year-old males. Sex was a significant factor affecting the content of Ca in the muscle and Zn in the exoskeleton. Age was a significant factor affecting the content of Zn, Cu, and Ca in the muscle and Zn and Cu in the exoskeleton. The bioconcentration factor (BCF) of Zn and Cu in the muscle and exoskeleton of spiny-cheek crayfish was much higher from water than from sediments, unlike Ca. Furthermore, we found significant correlation for muscle between Zn and total length in 3-year-old females and 4-year-old males and between Cu and TL in 3-year-old males. Analysing the recommended daily intake (RDI) for the investigated minerals confirmed that the consumption of 100 g of spiny-cheek crayfish muscle could meet daily requirement for Zn up to 27.5%, for Ca in 12.4%, and over 100% for Cu. The conducted analyses confirmed that the consumption of crayfish meat was safe for the health of potential consumers in terms of the analysed metal content.
Topics: Humans; Male; Animals; Female; Child, Preschool; Metals, Heavy; Astacoidea; Cheek; Environmental Monitoring; Water; Zinc; Water Pollutants, Chemical
PubMed: 36689108
DOI: 10.1007/s11356-023-25318-9 -
Journal of Invertebrate Pathology Jan 2021The occurrence of infectious diseases poses a significant threat to the aquaculture industry worldwide. Therefore, characterization of potentially harmful pathogens is...
The occurrence of infectious diseases poses a significant threat to the aquaculture industry worldwide. Therefore, characterization of potentially harmful pathogens is one of the most important strategies to control disease outbreaks. In the present study, we investigated for the first time the pathogenicity of two Vibrio species, Vibrio metschnikovii, a foodborne pathogen that causes fatalities in humans, and Vibrio areninigrae, a bacteria isolated from black sand in Korea, using a crustacean model, the signal crayfish Pacifastacus leniusculus. Mortality challenges indicated that injection of V. metschnikovii (10 CFU/crayfish) has a mortality percentage of 22% in crayfish. In contrast, injection of P. leniusculus with 10 or 10 CFU of V. areninigrae resulted in 100% mortality within one and two days post-injection, respectively. V. areninigrae was successfully re-isolated from hepatopancreas of infected crayfish and caused 100% mortality when reinjected into new healthy crayfish. As a consequence of this infection, histopathological analysis revealed nodule formation in crayfish hepatopancreas, heart, and gills, as well as sloughed cells inside hepatopancreatic tubules and atrophy. Moreover, extracellular crude products (ECP's) were obtained from V. areninigrae in order to investigate putative virulence factors. In vivo challenges with ECP's caused >90% mortalities within the first 24 h. In vitro challenges with ECP's of hemocytes induced cytotoxicity of hemocytes within the first hour of exposure. These findings represent the first report that V. areninigrae is a highly pathogenic bacterium that can cause disease in crustaceans. On the contrary, V. metschnikovii could not represent a threat for freshwater crayfish.
Topics: Animals; Astacoidea; Cytotoxins; Gills; Hemocytes; Hepatopancreas; Mortality; Republic of Korea; Seafood; Vibrio; Vibrio Infections
PubMed: 33333063
DOI: 10.1016/j.jip.2020.107517 -
Zootaxa Mar 2020The use of color photographs in crayfish species descriptions, state faunal books and popular articles is relatively recent. Except for verbal color descriptions, color...
The use of color photographs in crayfish species descriptions, state faunal books and popular articles is relatively recent. Except for verbal color descriptions, color and color patterns have not often been explored by crayfish researchers. Carotenoids and carotenoproteins are responsible for much of the color found in the integument and exoskeleton of crayfishes and other crustaceans. Research has shown variation in color may be the result of the environment, diet, molt stage and age, genetics, or a combination of these. Crayfishes possess color vision, may use polarization vision, and have the possibility of fluorescent vision. They also have very good low light vision. Crayfishes have a multichromatic range in color sensitivity; it ranges from blue to red, with no UV sensitivity. Color vision may be an important factor in intraspecific and interspecific competition, territoriality, camouflage, sexual selection, and communication. A distinction is made between base or background colors displayed in crayfishes and their exhibited color patterns. While actual base or background colors may vary among individual crayfishes, a case is made that color patterns show much less intraspecific variation. Distinct color patterns are the result of highly contrasting colors on appendages or parts of appendages such as chelae, leg joints, tail fan, spines, and tubercles. Body regions like the carapace and abdomen may also have contrasting spots, bands or stripes. Color patterns may be useful in better understanding crayfish taxonomy, phylogeny, and evolutionary convergence, and examples are provided.
Topics: Animals; Astacoidea; Color; Phylogeny; Vision, Ocular
PubMed: 32230194
DOI: 10.11646/zootaxa.4755.1.3 -
Journal of Invertebrate Pathology Nov 2023Host-associated microbial communities are an important determinant of individual fitness and have recently been highlighted as one of the factors influencing the success...
Host-associated microbial communities are an important determinant of individual fitness and have recently been highlighted as one of the factors influencing the success of invasive species. Invasive hosts introduce their microbes into the new environment, and then both the host and its associated microbes enter into a series of interactions with the native macroscopic and microscopic biota. As these processes are largely unexplored, we aimed to compare the exoskeletal microbial communities of co-occurring and phylogenetically related crayfish: the native narrow-clawed crayfish Pontastacus leptodactylus and the invasive signal crayfish Pacifastacus leniusculus from the recently invaded Korana River, Croatia. The results of high-throughput 16S rRNA sequencing showed that the exoskeletal microbiome of both species is very diverse, significantly influenced by the local environment and dominated by low abundance bacterial families from the phylum Proteobacteria. Furthermore, the exoskeletal microbiomes of the crayfish species differed significantly in the composition and abundance of Amplicon Sequence Variants (ASVs), suggesting that they are to some extent shaped by species-specific intrinsic factors, despite sharing a common habitat. However, over 95% of the bacterial genera associated with the exoskeleton were detected in the exoskeleton samples of both native and invasive crayfish. We paid particular attention to two known crayfish pathogens, Aphanomyces astaci and Saprolegnia parasitica, and find that both species carry low amounts of both pathogens. On the side, we find that a non-standard ddPCR protocol outperforms standard qPCR test for A. astaci under low concentration conditions. Taken together, our results indicate the possibility of bidirectional mixing and homogenisation of exoskeleton microbiome. As such, they can serve as a baseline in future detangling of the processes that act together to shape the microbiomes of co-occuring native and invasive congeners during biological invasions.
Topics: Humans; Animals; Astacoidea; Introduced Species; Exoskeleton Device; RNA, Ribosomal, 16S; Aphanomyces; Microbiota
PubMed: 37783231
DOI: 10.1016/j.jip.2023.107996 -
Journal of Invertebrate Pathology Jul 2023Crayfish have strong ecological impacts in freshwater systems, yet our knowledge of their parasites is limited. This study describes the first systemic microsporidium...
Crayfish have strong ecological impacts in freshwater systems, yet our knowledge of their parasites is limited. This study describes the first systemic microsporidium (infects multiple tissue types) Alternosema astaquatica n. sp. (Enterocytozoonida) isolated from a crayfish host, Faxonius virilis, using histopathology, transmission electron microscopy, gene sequencing, and phylogenetics. The parasite develops in direct contact with the host cell cytoplasm producing mature spores that are monokaryotic and ellipsoid in shape. Spores have 9-10 coils of the polar filament and measure 3.07 ± 0.26 µm (SD) in length and 0.93 ± 0.08 µm (SD) in width. Our novel isolate has high genetic similarity to Alternosema bostrichidis isolated from terrestrial beetles; however, genetic data from this parasite is restricted to a small fragment (396 bp) of the SSU gene. Additional data related to spore morphology and development, host, environment, and ecology indicate that our novel isolate is distinct from A. bostrichidis, which supports a new species description. Alternosema astaquatica n. sp. represents a novel member of the Orthosomella-like group which appears to be a set of opportunists within the Enterocytozoonida. The presence of this microsporidium in F. virilis could be relevant for freshwater ecosystems across this crayfish's broad geographic range in North America and may affect interactions between F. virilis and invasive rusty crayfish Faxonius rusticus in the Midwest USA.
Topics: Animals; Microsporidia; Parasites; Astacoidea; Ecosystem; Phylogeny
PubMed: 37276935
DOI: 10.1016/j.jip.2023.107948 -
Toxins Jul 2023Bacterial lipopolysaccharide (LPS) in the aquatic environment has been reported to cause diseases in red swamp crayfish (). In addition, deoxynivalenol (DON) is one of...
Bacterial lipopolysaccharide (LPS) in the aquatic environment has been reported to cause diseases in red swamp crayfish (). In addition, deoxynivalenol (DON) is one of the primary mycotoxins found in aquaculture. However, the potential synergistic toxic effects of LPS and DON on crayfish are yet to be fully elucidated. In this study, crayfish were exposed to LPS (1 mg kg), DON (3 mg kg), and their combination (1 mg kg LPS + 3 mg kg DON, L+D) for a duration of six days. Co-exposure to LPS and DON exhibited the lowest survival rate compared to the control or individual treatments with LPS or DON alone. In the initial stage of the experiment, the combined treatment of LPS and DON showed a more pronounced up-regulation of antioxidant and immune-related enzymes in the sera compared to the other treatment groups, with a fold change ranging from 1.3 to 15. In addition, the (L+D) treatment group showed a down-regulation of immune-related genes, as well as Toll pathway-related genes in the hepatopancreas compared to LPS or DON. Moreover, the (L+D) treatment group demonstrated a 100% incidence of histopathological changes in the hepatopancreas, which were significantly more severe compared to the other three groups. In conclusion, our study provides physiological and histopathological evidence that the co-exposure to LPS and DON exerted synergistic toxic effects on crayfish. The observed effects could potentially hinder the development of the crayfish aquaculture industry in China.
Topics: Animals; Antioxidants; Astacoidea; Lipopolysaccharides; Immunity
PubMed: 37624236
DOI: 10.3390/toxins15080479