Comprehensive Transcriptomic Analysis of Mouse Gonadal Development Involving Sexual Differentiation, Meiosis and Gametogenesis.

BACKGROUND: Mammalian gonadal development is crucial for fertility. Sexual differentiation, meiosis and gametogenesis are critical events in the process of gonadal development. Abnormalities in any of these events may cause infertility. However, owing to the complexity of these developmental events, the underlying molecular mechanisms are not fully understood and require further research. RESULTS: In this study, we employed RNA sequencing to examine transcriptome profiles of murine female and male gonads at crucial stages of these developmental events. By bioinformatics analysis, we identified a group of candidate genes that may participate in sexual differentiation, including Erbb3, Erbb4, and Prkg2. One hundred and two and 134 candidate genes that may be important for female and male gonadal development, respectively, were screened by analyzing the global gene expression patterns of developing female and male gonads. Weighted gene co-expression network analysis was performed on developing female gonads, and we identified a gene co-expression module related to meiosis. By alternative splicing analysis, we found that cassette-type exon and alternative start sites were the main forms of alternative splicing in developing gonads. A considerable portion of differentially expressed and alternatively spliced genes were involved in meiosis. CONCLUSION: Taken together, our findings have enriched the gonadal transcriptome database and provided novel candidate genes and avenues to research the molecular mechanisms of sexual differentiation, meiosis, and gametogenesis. SUPPLEMENTARY INFORMATION: Supplementary information accompanies this paper at 10.1186/s12575-019-0108-y.

Unequal distribution of 16S mtrRNA at the 2-cell stage regulates cell lineage allocations in mouse embryos.

Cell lineage determination during early embryogenesis has profound effects on adult animal development. Pre-patterning of embryos, such as that of Drosophila and Caenorhabditis elegans, is driven by asymmetrically localized maternal or zygotic factors, including mRNA species and RNA binding proteins. However, it is not clear how mammalian early embryogenesis is regulated and what the early cell fate determinants are. Here we show that, in mouse, mitochondrial ribosomal RNAs (mtrRNAs) are differentially distributed between 2-cell sister blastomeres. This distribution pattern is not related to the overall quantity or activity of mitochondria which appears equal between 2-cell sister blastomeres. Like in lower species, 16S mtrRNA is found to localize in the cytoplasm outside of mitochondria in mouse 2-cell embryos. Alterations of 16S mtrRNA levels in one of the 2-cell sister blastomere via microinjection of either sense or anti-sense RNAs drive its progeny into different cell lineages in blastocyst. These results indicate that mtrRNAs are differentially distributed among embryonic cells at the beginning of embryogenesis in mouse and they are functionally involved in the regulation of cell lineage allocations in blastocyst, suggesting an underlying molecular mechanism that regulates pre-implantation embryogenesis in mouse.

Design, synthesis and discovery of 5-hydroxyaurone derivatives as growth inhibitors against HUVEC and some cancer cell lines.

A series of 4'-substituted 5-hydroxyaurone derivatives were synthesized and their inhibitory activities against the proliferation of endothelial cells and two cancer cell lines were studied. Some of these compounds functioned as potent inhibitors against the proliferation of endothelial cells and cancer cells but possessed much weaker cytotoxic activities against non-cancer cell line of CCC-HPF-1. It was demonstrated that two most active compounds 16 and 27 effectively inhibited in vitro endothelial cell motility and tube formation, which are basic properties of endothelial cells for angiogenesis. Moreover, 16 and 27 also showed significant activities against in vitro cancer cell invasion, indicating that they have potential to inhibit cancer metastasis. These composite results suggest that 4'-substituted 5-hydroxyaurone is indeed a candidate structural scaffold for anticancer agent targeting activated endothelial cells and fast-proliferating cancer cells.

[Preparation and detection of phosphorylated PRAS40 (Ser183) polyclonal antibody].

PRAS40 (proline-rich Akt substrate 40 kD) associates with mammalian target of rapamycin complex 1(mTORC1), serine 183 site (Ser183) of PRAS40 can be phosphorylated by mTORC1. To prepare the phosphorylated PRAS40 (Ser183) antibody, We chosen 10-amino acid including Ser183 as antigen peptide through antigenicity and hydrophobicity analysis, hinged on keyhole limpet hemocyanin (KLH), and used the KLH-peptide to immunize rabbits. After antibody serum titer detection by enzyme linked immunosorbent assay (ELISA), the antibody was purified with rProtein A sepharose fast flow and dephosphorylated antigen membrane. The antibody titrate reached 1:10 000 after purification and its special property was enhanced with absorption treatment of dephosphorylated antigen membrane. In addition, we used rabbit anti-PRAS40 antibody and the phosphorylated PRAS40 (Ser183) antibody to detect PRAS40 expression in several cell lines, including the normal cells HL7702, HEK293, tumor cells HepG2, A549 and S180. There were no quite difference among these cells; otherwise, we observed the decreased phosphorylation level of Ser183 after amino acid withdrawal treatment. Therefore, the polyclonal phosphorylated PRAS40 (Ser183) antibody was specific to PRAS40 (Ser183) site and could be used for the function study of PRAS40.