Tissue-specific vitellogenesis and 17β-estradiol facilitate ovarian maturation of the swimming crab Portunus trituberculatus.

The present study investigated the changes of expression and localization of PtVg mRNA, tissue Vg/ Vn concentrations, the contents of progesterone and 17ß-estradiol during the ovarian development of P. trituberculatus. The results showed that: 1) The most abundant mRNA levels of PtVg were found in stage IV, and hepatopancreatic PtVg mRNA was markedly greater than that in ovaries from stage II to stage V.

Metabolomics Analysis Reveals Bitter Taste Formation in off-Season Crab Hepatopancreas Marketed in June of the Lunar Calendar.

Crabs marketed off-season in lunar June often have a brown hepatopancreas (BH) that tastes bitter, unlike the nonbitter orange hepatopancreas (OH). We conducted nontargeted and widely targeted metabolomics analyses on both raw and cooked orange and brown hepatopancreas of . A total of 115 bitter metabolites were identified, including oxylipins, amino acids, small peptides, nucleotides, vitamins, and coenzymes.

Occurrence and distribution of microplastics in freshwater aquaculture area with different culture modes in Yangtze River Delta of China.

There are multiple sources of microplastic contamination in freshwater aquaculture areas, such as water inputs, use of plastic farming tools and weathering of discarded plastics, leading to microplastic contamination of aquaculture environments, but microplastics in freshwater aquaculture areas are still limited. In our study, we investigated the distribution of microplastics (MPs) in the aquaculture water, sediments and crabs during the growth cycle of crabs with different culture modes. The results show that from May to October, MPs in surface water first increased and then decreased, which is related to water evaporation and river water recharge caused by local hot and sunny weather.

NinaB and BCO Collaboratively Participate in the β-Carotene Catabolism in Crustaceans: A Case Study on Chinese Mitten Crab .

Carotenoid cleavage oxygenases can cleave carotenoids into a range of biologically important products. Carotenoid isomerooxygenase (NinaB) and β, β-carotene 15, 15'-monooxygenase (BCO1) are two important oxygenases. In order to understand the roles that both oxygenases exert in crustaceans, we first investigated () and () within the genome of Chinese mitten crab ().

Insights into sequence characteristics and evolutionary history of DGATs in arthropods.

Triacylglycerol (TAG) is crucial in animal energy storage and membrane biogenesis. The conversion of diacylglycerol (DAG) to triacylglycerol (TAG) is catalyzed by diacylglycerol acyltransferase enzymes (DGATs), which are encoded by genes belonging to two distinct gene families. Although arthropods are known to possess DGATs activities and utilize the glycerol-3-phosphate pathway and MAG pathway for TAG biosynthesis, the sequence characterization and evolutionary history of DGATs in arthropods remains unclear.

The comparison of morphology and transcriptome in the inner membrane reveals the potential mechanism of the heritable carapace color of the Chinese mitten crab Eriocheir sinensis.

Carapace color plays an important role in the communication, reproduction, and self-defense of crustaceans, which is also related to their economic value. Chinese mitten crab (Eriocheir sinensis) is an important aquaculture species in China, and there are different strains with heritable carapace colors, i.e.

Evolution and expression analysis of carotenoid cleavage oxygenase gene family in Chinese mitten crab Eriocheir sinensis.

Carotenoid cleavage oxygenase (CCO) plays a pivotal role in various biological activities, including antioxidant and immune functions in animals. This paper investigates the evolution and expression of CCO genes based on three chordates and 27 arthropods. Aquatic animals exhibit a higher abundance of CCO genes.

Metabolome and Transcriptome Association Analysis Reveals the Link Between Pigmentation and Nutrition Utilization in the Juveniles of Sea Cucumber Holothuria leucospilota.

The sea cucumber Holothuria leucospilota is an economically and ecologically important tropical species. Following development into juveniles, H. leucospilota undergoes a color change from white to black, involving a pigmentation process for over a period of several months.

Expression pattern of AGPATs isoforms indicate different functions during the triacylglyceride synthesis in Chinese mitten crab, Eriocheir sinensis.

The 1-acylglycerol-3-phosphate acyltransferase (AGPAT) acts as a crucial enzyme in the process of triacylglycerol (TAG) synthesis, enabling the acylation of lysophosphatidic acid (LPA) into phosphatidic acid (PA). In order to decode the distinctive roles of AGPAT isoforms in the TAG production pathway, three AGPAT isoforms were detected for the first time in the Chinese mitten crab Eriocheir sinensis (Es-agpat2, Es-agpat3, and Es-agpat4). The mRNA levels of Es-agpat2 and Es-agpat4 demonstrated a conspicuous presence in the hepatopancreas, with subsequent high levels in the heart, muscle, and thoracic ganglion.

Comparative proteomics elucidates the potential mechanism of heritable carapace color of three strains Chinese mitten crab Eriocheir sinensis.

The carapace coloration is important for the environmental adaptation and reproductive behaviors of crustaceans. We selected red, green and white three carapace color strains of Chinese mitten crab (Eriocheir sinensis) strains. These three carapace colors have stable heritability, but the mechanism for their coloration remains unclear.

Dietary supplementation with synthetic astaxanthin and DHA interactively regulates physiological metabolism to improve the color and odor quality of ovaries in adult female Eriocheir sinensis.

The present study aimed to investigate the interactive effects of dietary supplementation to the feed with astaxanthin and/or DHA on the color and odor of Eriocheir sinensis ovaries. The results revealed that astaxanthin supplementation significantly increased redness of E. sinensis ovaries (P < 0.

Functional transcriptome reveals hepatopancreatic lipid metabolism during the molting cycle of the Chinese mitten crab Eriocheir sinensis.

Crustacean molting is highly related to energy and lipid metabolism. This study was conducted to detect the changes of total lipids (TL), triacylglyceride (TAG), phospholipid (PL) and lipid droplets in hepatopancreas, and then to investigate the gene expression patterns related to hepatopancreatic lipid metabolism during the molting cycle of Chinese mitten crab Eriocheir sinensis. Hepatopancreatic TL and TAG increased significantly from post-molt stage to pre-molt stage, then decreased significantly from pre-molt stage to ecdysis stage, which is consistent to the changes of neutral lipid-rich adipocytes in hepatopancreas.

Control of phosphorus release from sediment by hydrous zirconium oxide combined with calcite, bentonite and zeolite.

This study investigated the effectiveness and mechanism for the control of internal phosphorus (P) liberation from sediment by hydrous zirconium oxide (HZrO) combined with calcite, bentonite and zeolite. The results suggested that coexisting calcite, calcium-modified bentonite (CaBT) and calcium-modified zeolite (CaZ) all had the ability to promote the adsorption of phosphate (PO) onto HZrO. The mechanisms of PO elimination by HZrO/calcite mixture involved the adsorption of PO on calcite, the precipitation of PO with Ca, and the inner-sphere complexation of PO with HZrO.

Combined amendment and capping of sediment with ferrihydrite and magnetite to control internal phosphorus release.

This study developed novel active capping systems with recycling convenience using ferrihydrite (Fh) combined with magnetite (Mag), and investigated the effectiveness and mechanism for the restriction of endogenous phosphorus movement from sediment into overlying water (OW) by the combined use of Fh and Mag. The Fh/Mag combined amendment effectively hindered endogenous phosphorus release from sediment to OW in dissolved oxygen (DO)-deficit environment, and the immobilization of diffusion gradient in thin film-labile phosphorus (LP) and mobile phosphorus in the sediment played a key role in the control of endogenous phosphorus liberation by the Fh/Mag combined amendment. Combined capping sediment with Fh and Mag effectively hindered endogenous phosphorus release from sediment to OW in anoxic environment, and the inactivation of LP in the upper sediment played a key part in the control of sediment phosphorus release by the Fh/Mag mixture capping.

Occurrence and distribution characteristics of aged microplastics in the surface water, sediment, and crabs of the aquaculture pond in the Yangtze River Delta of China.

The artificial breeding of freshwater crabs in China has become the main source, accounting for 45.69 % of the total output in 2020. However, microplastics widely exist in ponds due to the addition of meals, and the aging and breakage of plastic tools, and people know little about the occurrence of microplastics in the environment and the tissues of crabs during the cultivation of crabs in ponds.

Changes in Protein Degradation and Non-Volatile Flavor Substances of Swimming Crab () during Steaming.

To investigate the effect of steaming time (0, 5, 10, 15, 20, and 25 min) on the protein degradation and non-volatile flavor substances of swimming crab (), the moisture content, total nitrogen (TN), non-protein nitrogen (NPN), free amino acids (FAAs), flavor nucleotides, electronic tongue analysis, and sensory evaluation were determined. The results showed that the contents of NPN and total FAAs were the highest after crabs steamed for 10 min. Meanwhile, the AMP (adenosine monophosphate) content reached the maximum value (332.

Pacific white shrimp (Litopenaeus vannamei) vitelline membrane outer layer protein 1 (VMO1) is produced in the hepatopancreas and transported into ovarian oocytes during vitellogenesis.

In birds, vitelline membrane outer layer protein 1 (VMO1) is an exogenous protein that can be absorbed by eggs as a barrier to prevent the mixing of yolk and egg white. However, researches on VMO1 are limited in birds but not other non-avian species until now. In this study, we first identified a novel Vmo1 cDNA (Lv-Vmo1) in Pacific white shrimp (Litopenaeus vannamei), the most important cultured shrimp in the world.

Comparative study of female Chinese mitten crabs based on their sizes and weights.

The Chinese mitten crab () is an important aquaculture species in China. While the price of a large crab will generally be 2-5 times higher than that of smaller crabs, it remains unknown whether nutritional quality is affected by market price. To investigate the effect of size on nutritional composition, adult female crabs were collected and assigned to grades I-IV according to decreasing size.

Comparative Transcriptome Analysis Reveals the Process of Ovarian Development and Nutrition Metabolism in Chinese Mitten Crab, .

Ovarian development is a key physiological process that holds great significance in the reproduction of the Chinese mitten crab (), which is an economically important crab species for aquaculture. However, there is limited knowledge for the regulatory mechanisms of ovarian development. To study the molecular mechanisms of its ovarian development, transcriptome analysis was performed in the ovary and hepatopancreas of during ovarian stages I (oogonium proliferation), II (endogenous vitellogenesis), and III (exogenous vitellogenesis).

Comparative Analyses of Scylla olivacea Gut Microbiota Composition and Function Suggest the Capacity for Polyunsaturated Fatty Acid Biosynthesis.

Although numerous studies in aquatic organisms have linked lipid metabolism with intestinal bacterial structure, the possibility of the gut microbiota participating in the biosynthesis of beneficial long-chain polyunsaturated fatty acid (LC-PUFA) remains vague. We profiled the gut microbiota of the mud crab Scylla olivacea fed with either a LC-PUFA rich (FO) or a LC-PUFA-poor but C18-PUFA substrate-rich (LOCO) diet. Additionally, a diet with a similar profile as LOCO but with the inclusion of an antibiotic, oxolinic acid (LOCOAB), was also used to further demarcate the possibility of LC-PUFA biosynthesis in gut microbiota.

Population genetic analysis reveals secondary contact between Eriocheir sinensis and E. japonica in South Korea.

Background: The Chinese mitten crab (Eriocheir sinensis) and the Japanese mitten crab (E. japonica) of the family Varunidae, which are also critical fishery species in their native habitats, including China, Japan, and South Korea, exhibit a rare migration life history for the decapod life cycle. Eriocheir sinensis and E.