Heat Shock Proteins and Maternal Contribution to Oogenesis and Early Embryogenesis

The transcription factor masculinizer in sexual differentiation and achieved full functional sex reversal in prawn

Some Zinc finger (ZnF) proteins are required for masculinization in silkworms. In the present study, a masculinizer gene (Mr-Masc) with multi-tissue expression is identified in the freshwater prawn Macrobrachium rosenbergii. The Mr-Masc is clustered into a separate branch with ZnF proteins from decapoda by phylogenetic tree analysis. Moreover, Mr-Masc silencing in male postlarvae prawn results in functional sex reversal females known as neo-females, which are applied to all-male monosex offspring breeding. This manipulation has been significant in sexually dimorphic cultured species. In addition, several significantly expressed transcripts are enriched and the effects of crucial signal pathways are focused through the comparative transcriptomic analysis in Mr-Masc gene knockdown. The significantly differentially expressed epidermal growth factor, upregulated low-density lipoprotein receptor, flotillin, and sex-lethal unigenes, downregulated heat shock proteins and forkhead box homologs are focused. The finding offers an innovative perspective on Masc proteins' evolution and physiological function.

Heat Shock Factors in Protein Quality Control and Spermatogenesis

Proper regulation of cellular protein quality control is crucial for cellular health. It appears that the protein quality control machinery is subjected to distinct regulation in different cellular contexts such as in somatic cells and in germ cells. Heat shock factors (HSFs) play critical role in the control of quality of cellular proteins through controlling expression of many genes encoding different proteins including those for inducible protein chaperones. Mammalian cells exert distinct mechanism of cellular functions through maintenance of tissue-specific HSFs. Here, we have discussed different HSFs and their functions including those during spermatogenesis. We have also discussed the different heat shock proteins induced by the HSFs and their activities in those contexts. We have also identified several small molecule activators and inhibitors of HSFs from different sources reported so far.

Full Functional Sex Reversal Achieved Through Silencing of MroDmrt11E Gene in Macrobrachium rosenbergii: Production of All-Male Monosex Freshwater Prawn

The freshwater prawn Macrobrachium rosenbergii is one kind of important economic aquaculture species and displays remarkable sexual dimorphism. The molecular mechanism of sexual differentiation in M. rosenbergii has been primarily unraveled through the research efforts of the androgenic gland and its related genes. However, the understanding of conserved genes involved in the molecular mechanism underpinning sex determination and sexual differentiation of M. rosenbergii is still fragmentary. MroDmrt11E is a member of the doublesex and mab-3-related transcription factor (Dmrt) gene family and is prominently expressed in the testis. In the present study, in vivo knockdown of MroDmrt11E at the postlarva stage in male prawn induced a complete and functional sex reversal and achieved the production of an all-male monosex population. Furthermore, a great deal of new information of upregulated and downregulated transcriptions involved in sexual differentiation of MroDmrt11E knockdown was enriched by comparative transcriptomic analysis. The effects of RNAi-mediated gene knockdown of MroDmrt11E on the differentially expressed and sex-related candidate genes, such as transformer, fruitless, feminization, insulin-like androgenic gland gene, Dmrt gene family, were primarily focused on, and their possible molecular regulatory relationships in sexual differentiation were analyzed. Meanwhile, the response of primary Kyoto Encyclopedia of Genes and Genomes (KEGG) biological pathways was investigated to expound the potential roles of MroDmrt11E in male sexual differentiation, which provided a deeper understanding of the molecular regulatory network underlying sexual differentiation of M. rosenbergii. The finding provided a novel sexual manipulation technique through silencing of Dmrt gene family for achieving a complete and functional sex reversal and offered a new insight regarding the mechanism of the Dmrt gene family in the sexual differentiation of crustaceans.