Functional characterization of MrOrb in Macrobrachium rosenbergii reveals its crucial role in spermatogenesis.

Orb proteins, members of the cytoplasmic polyadenylation element-binding (CPEB) family, play critical roles in germline development in various organisms. Studies in Drosophila melanogaster have indicated that Orb genes are essential for oocyte development, and are crucial for spermatogenesis, including meiotic completion and spermatid differentiation. However, their role in crustacean spermatogenesis remains largely unexplored.

Identifying sex-chromosome-linked determinants of sexual differentiation in a WZ-ZZ sex inheritance crustacean†.

Sex determination triggers transcriptional cascades, leading to the development of male or female phenotypes. The aim of this study was to shed light on the linkage between sex determination and sexual differentiation by identifying key W/Z-linked elements that control sexual differentiation in crustaceans with the WZ-ZZ mode of sex inheritance. To this end, we leveraged our previous studies on the insulin-like androgenic gland (IAG) hormone, which serves as a master switch - termed the "IAG switch" - in the freshwater prawn Macrobrachium rosenbergii, in which manipulations of the IAG-switch afforded functional WZ males, ZZ females, and even WW males and females.

Cuticular proteins (crusticuls) affect 3D chitin bundle nanostructure.

The crustacean exoskeleton features a micrometric, three-dimensional chitin scaffold. The intricate organization of this structure makes it an ideal model for investigating scaffold proteins at the nanoscale. Periodic exoskeleton replacement during a rapid and punctual molt cycle involves proteins that govern exoskeleton formation.

First evidence of molecular response of the shrimp Hippolyte inermis to biodegradable microplastics.

The increasing demand for sustainable alternatives to conventional plastics has propelled the interest in bioplastics. A few papers reported on the effects of plastics on crustaceans, but no indication about biodegradable polymers is available. Hippolyte inermis Leach, 1816 is a protandric shrimp commonly living on leaves of the seagrass Posidonia oceanica, in the Mediterranean Sea.

Roadmap and Considerations for Genome Editing in a Non-Model Organism: Genetic Variations and Off-Target Profiling.

The CRISPR/Cas genome editing approach in non-model organisms poses challenges that remain to be resolved. Here, we demonstrated a generalized roadmap for a de novo genome annotation approach applied to the non-model organism . We also addressed the typical genome editing challenges arising from genetic variations, such as a high frequency of single nucleotide polymorphisms, differences in sex chromosomes, and repetitive sequences that can lead to off-target events.

Characterization of a novel and testis-specific zinc finger protein during sexual development of Pacific white shrimp Litopenaeus vannamei†.

Since females grow faster in penaeid shrimp, all-female aquaculture was proposed. Environmental conditions in the Pacific white shrimp were not found to affect genetic sex determination (ZZ/ZW system). The androgenic gland-secreting insulin-like androgenic gland hormone is a key controlling factor in crustacean male differentiation.

Molecular Approaches Detect Early Signals of Programmed Cell Death in Leach.

The protandric shrimp is the only known marine invertebrate whose sex determination is strongly influenced by the composition of its food. In , a sex reversal is triggered by the ingestion of diatoms of the genus associated with leaves of the seagrass . These diatoms contain compounds that promote programmed cell death (PCD) in and also in human cancer cells.

A transporter that allows phosphate ions to control the polymorph of exoskeletal calcium carbonate biomineralization.

The SLC20A2 transporter supplies phosphate ions (P) for diverse biological functions in vertebrates, yet has not been studied in crustaceans. Unlike vertebrates, whose skeletons are mineralized mainly by calcium phosphate, only minute amounts of P are found in the CaCO-mineralized exoskeletons of invertebrates. In this study, a crustacean SLC20A2 transporter was discovered and P transport to exoskeletal elements was studied with respect to the role of P in invertebrate exoskeleton biomineralization, revealing an evolutionarily conserved mechanism for P transport in both vertebrates and invertebrates.

Regulation of early spermatogenesis in the giant prawn Macrobrachium rosenbergii by a GCL homolog†.

The germ cell-less gene is crucial for gonad development in various organisms. Early interventions in its expression suggested a regulatory role at the mitotic stages of spermatogenesis, and its early knockout resulted in complete sterility in Drosophila. Genomic and transcriptomic data available for the catadromous giant prawn Macrobrachium rosenbergii enabled the identification of a germ cell-less homolog for this species, which we termed MroGCL (mRNA accession number OQ533056).

Monosex Populations of the Giant Freshwater Prawn -From a Pre-Molecular Start to the Next Generation Era.

Sexual manipulation in the giant freshwater prawn has proven successful in generating monosex (both all-male and all-female) populations for aquaculture using a crustacean-specific endocrine gland, the androgenic gland (AG), which serves as a key masculinizing factor by producing and secreting an insulin-like AG hormone (IAG). Here, we provide a summary of the advancements from the discovery of the AG and IAG in decapods through to the development of monosex populations in . We discuss the broader sexual development pathway, which is highly divergent across decapods, and provide our future perspective on the utility of novel genetic and genomic tools in promoting refined approaches towards monosex biotechnology.

Ferroptosis precedes apoptosis to facilitate specific death signalling by fatty acids.

Cell death is physiologically induced by specific mediators. However, our power to trigger the process in selected cells is quite limited. The protandric shrimp offers a possible answer.

A tunable reflector enabling crustaceans to see but not be seen.

Many oceanic prey animals use transparent bodies to avoid detection. However, conspicuous eye pigments, required for vision, compromise the organisms' ability to remain unseen. We report the discovery of a reflector overlying the eye pigments in larval decapod crustaceans and show how it is tuned to render the organisms inconspicuous against the background.

Genes Encoding the Glycoprotein Hormone GPA2/GPB5 and the Receptor LGR1 in a Female Prawn.

In vertebrate reproduction, metabolism, growth and development, essential roles are played by glycoprotein hormones, such as follicle-stimulating hormone (FSH), luteinizing hormone (LH) and thyroid-stimulating hormone (TSH), all of which are heterodimers consisting of two subunits, a structurally identical alpha subunit, and a variable beta subunit, which provides specificity. A 'new' glycoprotein hormone heterodimer identified in both vertebrates and invertebrates, including decapod crustaceans, was shown to be composed of the glycoprotein alpha 2 (GPA2) and glycoprotein beta 5 (GPB5) subunits. The putative receptor for GPA2/GPB5 in invertebrates is the leucine-rich repeat-containing G protein-coupled receptor 1 (LGR1).

Corrigendum: Sex-Biased CHHs and Their Putative Receptor Regulate the Expression of IAG Gene in the Shrimp .

[This corrects the article DOI: 10.3389/fphys.2019.

Genes encoding putative bicarbonate transporters as a missing molecular link between molt and mineralization in crustaceans.

During their life, crustaceans undergo several molts, which if theoretically compared to the human body would be equivalent to replacing all bones at a single event. Such a dramatic repetitive event is coupled to unique molecular mechanisms of mineralization so far mostly unknown. Unlike human bone mineralized with calcium phosphate, the crustacean exoskeleton is mineralized mainly by calcium carbonate.

Hemocyanin Modification of Chitosan Scaffolds with Calcium Phosphate Phases Increase the Osteoblast/Osteoclast Activity Ratio-A Co-Culture Study.

The ongoing research on biomaterials that support bone regeneration led to the quest for materials or material modifications that can actively influence the activity or balance of bone tissue cells. The bone biocompatibility of porous chitosan scaffolds was modified in the present study by the addition of calcium phosphates or hemocyanin. The first strategy comprised the incorporation of calcium phosphates into chitosan to create a biomimetic chitosan-mineral phase composite.

The "IAG-Switch"-A Key Controlling Element in Decapod Crustacean Sex Differentiation.

The androgenic gland (AG)-a unique crustacean endocrine organ that secretes factors such as the insulin-like androgenic gland (IAG) hormone-is a key player in crustacean sex differentiation processes. IAG expression induces masculinization, while the absence of the AG or a deficiency in IAG expression results in feminization. Therefore, by virtue of its universal role as a master regulator of crustacean sexual development, the IAG hormone may be regarded as the sexual "IAG-switch.

From sporadic single genes to a broader transcriptomic approach: Insights into the formation of the biomineralized exoskeleton in decapod crustaceans.

One fundamental character common to pancrustaceans (Crustacea and Hexapoda) is a mineralized rigid exoskeleton whose principal organic components are chitin and proteins. In contrast to traditional research in the field that has been devoted to the structural and physicochemical aspects of biomineralization, the present study explores transcriptomic aspects of biomineralization as a first step towards adding a complementary molecular layer to this field. The rigidity of the exoskeleton in pancrustaceans dictates essential molt cycles enabling morphological changes and growth.

Characterization and possible function of an enigmatic reflector in the eye of the shrimp .

Reflective assemblies of high refractive index organic crystals are used to produce striking optical phenomena in organisms based on light reflection and scattering. In aquatic animals, organic crystal-based reflectors are used both for image-formation and to increase photon capture. Here we report the characterization of a poorly-documented reflector in the eye of the shrimp L.

The protandric life history of the Northern spot shrimp Pandalus platyceros: molecular insights and implications for fishery management.

The Northern spot shrimp, Pandalus platyceros, a protandric hermaphrodite of commercial importance in North America, is the primary target species for shrimp fisheries within Southeast Alaska. Fishery data obtained from the Alaska Department of Fish and Game indicate that spot shrimp populations have been declining significantly over the past 25 years. We collected spot shrimps in Southeast Alaska and measured reproductive-related morphological, gonadal and molecular changes during the entire life history.

A highly reflective biogenic photonic material from core-shell birefringent nanoparticles.

Spectacular natural optical phenomena are produced by highly reflective assemblies of organic crystals. Here we show how the tapetum reflector in a shrimp eye is constructed from arrays of spherical isoxanthopterin nanoparticles and relate the particle properties to their optical function. The nanoparticles are composed of single-crystal isoxanthopterin nanoplates arranged in concentric lamellae around a hollow core.