Transcriptome analysis of the post-larvae of giant freshwater prawn (Macrobrachium rosenbergii) after IAG gene knockdown with microRNA interference.

The insulin-like androgenic gland hormone gene (IAG) of crustaceans plays pivotal roles in the regulation of sex differentiation. MicroRNAs (miRNAs) are a class of short, non-coding RNAs that function as post-transcriptional gene regulators. However, little information about the regulatory relationship between miRNA and Macrobrachium rosenbergii IAG (MrIAG) were exposed. In this study, we used the 3' untranslated region (UTR) of MrIAG to predict potential target sites of miRNAs. The results showed that miR-184 has one target site in the 3'UTR of MrIAG. Dual-luciferase report assay in vitro confirmed that miR-184 can significantly down-regulate MrIAG expression. Besides, we constructed mutant plasmids of 3'UTR of MrIAG. The result displayed that after co-transfection of mutant plasmids and miR-184 agomir, the activity of luciferase was not affected compared to the control. These results indicated that miR-184 could directly regulate MrIAG. In addition, we found that overexpression of miR-184 in M. rosenbergii can lead to significant changes in the transcription level of genes. Compared with control group, we identified 1510 differentially expressed genes (DEGs) in the miR-184 injection group. Some DEGs were involved in sex differentiation, gonad development, growth and molting were found. qRT-PCR verification was performed on eight DEGs randomly, and the results showed that the expression level of sex-, growth-, and metabolism-related genes changed significantly after MrIAG gene knockdown. Collectively, findings from this study suggest that miR-184, by mediating IAG expression, may be involved in many physiological processes in M. rosenbergii. The current study lays a basic understanding for short-term silencing of MrIAG with miR-184, and facilitates miRNA function analysis in M. rosenbergii in future.

AgNPs reduce reproductive capability of female mouse for their toxic effects on mouse early embryo development.

Silver nanoparticles (AgNPs) are widely applied in the field of personal protection for their powerful toxic effects on cells, and recently, a new type of vaginal gel with AgNPs is used to protect the female reproductive tract from microbes and viruses. However, a high risk of AgNPs to the fetus and the underlying mechanism of AgNPs to interfere in embryo development still remain unclear. Thus, this study investigated the impact of two drugs of vaginal gel with AgNPs on reproductive capability of the female mouse by animal experiment. Then, kinetics of AgNPs affecting embryo development was investigated by in vitro embryos culturing, and cell membrane potential (CMP) of zygotes was analyzed by DiBAC4(3) staining. Results indicated that one of the drugs of vaginal gel certainly injured embryo development in spite of no apparent histological change found in ovaries and uteruses of drug-treated mice. In vitro embryo culturing discovered that the toxic effect of AgNPs on embryo development presented particle sizes and dose dependent, and AgNP treatment could rapidly trigger depolarization of the cell membrane of zygotes. Moreover, AgNPs changed the gene expression pattern of Oct-4 and Cdx2 in blastocysts. All these findings suggest that AgNPs can interfere with normal cellular status including cell membrane potential, which has not been noticed in previous studies on the impact of AgNPs on mammalian embryos. Thus, findings of this study alarm us the risk of applying vaginal gel with AgNPs in individual caring and protection of the female reproductive system.

AgNPs reduce reproductive capability of female mouse for their toxic effects on mouse early embryo development.

Silver nanoparticles (AgNPs) are widely applied in the field of personal protection for their powerful toxic effects on cells, and recently, a new type of vaginal gel with AgNPs is used to protect the female reproductive tract from microbes and viruses. However, a high risk of AgNPs to the fetus and the underlying mechanism of AgNPs to interfere in embryo development still remain unclear. Thus, this study investigated the impact of two drugs of vaginal gel with AgNPs on reproductive capability of the female mouse by animal experiment. Then, kinetics of AgNPs affecting embryo development was investigated by in vitro embryos culturing, and cell membrane potential (CMP) of zygotes was analyzed by DiBAC4(3) staining. Results indicated that one of the drugs of vaginal gel certainly injured embryo development in spite of no apparent histological change found in ovaries and uteruses of drug-treated mice. In vitro embryo culturing discovered that the toxic effect of AgNPs on embryo development presented particle sizes and dose dependent, and AgNP treatment could rapidly trigger depolarization of the cell membrane of zygotes. Moreover, AgNPs changed the gene expression pattern of Oct-4 and Cdx2 in blastocysts. All these findings suggest that AgNPs can interfere with normal cellular status including cell membrane potential, which has not been noticed in previous studies on the impact of AgNPs on mammalian embryos. Thus, findings of this study alarm us the risk of applying vaginal gel with AgNPs in individual caring and protection of the female reproductive system.

Comparative transcriptome analysis of the gills and hepatopancreas from Macrobrachium rosenbergii exposed to the heavy metal Cadmium (Cd2+).

Heavy metal Cadmium (Cd2+) pollution has become a severe environmental problem for aquatic organisms. In crustaceans, gills (Gi) and hepatopancreas (Hp) play a vital role in the toxicology. However, in Macrobrachium rosenbergill, there are few researches about gill and hepatopancreases responding to Cd2+ stress at a molecular level. In this study, transcriptomic analysis was applied to characterize gene expression profiles of gills and hepatopancreas of M. rosenbergill after Cd2+ exposure for 0 h, 3 h and 3 d. Six cDNA libraries (Gi 0 h, Gi 3 h, Gi 3 d, Hp 0 h, Hp 3 h, and Hp 3 d) were constructed and a total of 66,676 transcripts and 48,991 unigenes were annotated. Furthermore, differentially expressed genes (DEGs) were isolated by comparing the Cd2+ treated time-point libraries (3 h and 3 d group) with the control library (0 h group). The results showed that most of the DEGs were down-regulated after Cd2+ exposure and the number of DEGs among gill groups were significantly higher than those among hepatopancreas groups. GO functional and KEGG pathway analysis suggested many key DEGs in response to the Cd2+ stress, such as metallothionein and Hemocyanin. Additionally, a total of six DEGs were randomly selected to further identify their expressional profile by qPCR. The results indicated that these DEGs were involved in the response to Cd2+. This comparative transcriptome provides valuable molecular information on the mechanisms of responding to Cd2+ stress in M. rosenbergii, which lays the foundation for further understanding of heavy metal stress.

Transcriptional changes revealed water acidification leads to the immune response and ovary maturation delay in the Chinese mitten crab Eriocheir sinensis.

Nowadays, due to increasing carbon dioxide released, water acidification poses a series of serious impacts on aquatic organisms. To evaluate the effects of water acidification on crustaceans, we focused on the Chinese mitten crab Eriocheir sinensis, which is a spawning migration and farmed species in China. Based on histological and oocyte transparent liquid observation, we found that the acidified environment significantly delayed the ovarian maturation of E. sinensis. Moreover, RNA-seq was applied to obtain gene expression profile from the crab's gills and ovaries in response to acidified environment. Compared with control groups, a total of 5471 differentially expressed genes (DEGs) were identified in acidified gills and 485 DEGs were identified in acidified ovaries. Enrichment analysis indicated that some pathways also responded to the acidified environment, such as PI3K-Akt signaling pathway, Chemokine signaling pathway, apoptosis, and toll-like receptor signaling pathway. Subsequently, some DEGs involved in immune response (ALF, Cathepsin A, HSP70, HSP90, and catalase) and ovarian maturation (Cyclin B, Fem-1a, Fem-1b, and Fem-1c) were selected to further validate the influence of water acidification on gene expression by qRT-PCR. The results showed that the expression level of immune-related genes was significantly increased to response to the water acidification, while the ovarian maturation-related genes were significantly decreased. Overall, our data suggested that E. sinensis was sensitive to the reduced pH. This comparative transcriptome also provides valuable molecular information on the mechanisms of the crustaceans responding to acidified environment.