Inhibiting bridge integrator 2 phosphorylation leads to improved oocyte quality, ovarian health and fertility in aging and after chemotherapy in mice.

Female ovaries degenerate about 20 years earlier than testes leading to reduced primordial follicle reserve and a reduction in oocyte quality. Here we found that bridge integrator 2 (BIN2) is enriched in mouse ovaries and oocytes and that global knockout of this protein improves both female fertility and oocyte quality. Quantitative ovarian proteomics and phosphoproteomics showed that Bin2 knockout led to a decrease in phosphorylated ribosomal protein S6 (p-RPS6), a component of the mammalian target of rapamycin pathway and greatly increased nicotinamide nucleotide transhydrogenase (NNT), the free-radical detoxifier. Mechanistically, we find that phosphorylation of BIN2 at Thr423 and Ser424 leads to its translocation from the membrane to the cytoplasm, subsequent phosphorylation of RPS6 and inhibition of Nnt translation. We synthesized a BIN2-penetrating peptide (BPP) designed to inhibit BIN2 phosphorylation and found that a 3-week BPP treatment improved primordial follicle reserve and oocyte quality in aging and after chemotherapy-induced premature ovarian failure without discernible side effects.

FOXM1 contributes to docetaxel resistance in castration-resistant prostate cancer by inducing AMPK/mTOR-mediated autophagy.

Docetaxel-mediated chemotherapy is the first line therapy for metastatic castration-resistant prostate cancer (CRPC) patients, but its therapeutic benefit is limited by the development of resistance. Although Forkhead box protein M1 (FOXM1) has been implicated in prostate tumorigenesis and metastasis, its role in docetaxel resistance has not been studied. Here, we showed that FOXM1 expression was upregulated in the docetaxel resistant CRPC cell lines (PC3-DR and VCaP-DR) and knockdown of FOXM1 sensitized the cells to docetaxel both in vitro and in vivo. In addition, autophagy was found to be significantly enhanced in resistant cells. Moreover, FOXM1 overexpression cells showed increased autophagic flux and higher numbers of autophagosomes. Knockdown of ATG7, beclin-1 or cotreatment with chloroquine, partly restored sensitivity to docetaxel in the FOXM1-overexpressing cells. Mechanistically, FOXM1 targeted AMPK/mTOR to activate the autophagy pathway and altered docetaxel response in CRPC. These findings identify the role of FOXM1 as well as the mechanism underlying FOXM1 action in docetaxel sensitivity and may, therefore, aid in design of CRPC therapies.

Placenta-specific 1 regulates oocyte meiosis and fertilization through furin.

Placenta-specific 1 (Plac1) has been found to be essential for placentation, and abnormal Plac1 expression and distribution is highly correlated with preeclampsia and implantation failure; however, its function in mammalian oocytes has not been elucidated. Here, we report that Plac1 was more prominent in mouse oocytes and enriched at the membrane region throughout meiosis. On the one hand, Plac1 knockdown severely disrupted microvillus organization; however, on the other hand, Plac1 significantly decreased oocyte maturation and increased aneuploidy, consequently disrupting normal fertilization. On the basis of immunoprecipitate matrix-assisted laser desorption/ionization, we established a working model, then verified and suggested that, at the germinal vesicle stage, Plac1 enriches the membrane to activate furin, and active furin subsequently activates IGF-1 receptor to maintain regular microvillus organization. Upon meiosis onset, active furin/IGF-1 receptor relocates into the cytoplasm to activate (phosphorylate) Akt to promote meiosis. In summary, our finding suggests that Plac1, a protein that is crucial for placentation, is also essential for oocyte meiosis and fertilization.-Shi, L.-Y., Ma, Y., Zhu, G.-Y., Liu, J.-W., Zhou, C.-X., Chen, L.-J., Wang, Y., Li, R.-C., Yang, Z.-X., Zhang, D. Placenta-specific 1 regulates oocyte meiosis and fertilization through furin.

ZP3 is Required for Germinal Vesicle Breakdown in Mouse Oocyte Meiosis.

ZP3 is a principal component of the zona pellucida (ZP) of mammalian oocytes and is essential for normal fertility, and knockout of ZP3 causes complete infertility. ZP3 promotes fertilization by recognizing sperm binding and activating the acrosome reaction; however, additional cellular roles for ZP3 in mammalian oocytes have not been yet reported. In the current study, we found that ZP3 was strongly expressed in the nucleus during prophase and gradually translocated to the ZP. Knockdown of ZP3 by a specific siRNA dramatically inhibited germinal vesicle breakdown (GVBD) (marking the beginning of meiosis), significantly reducing the percentage of MII oocytes. To investigate the ZP3-mediated mechanisms governing GVBD, we identified potential ZP3-interacting proteins by immunoprecipitation and mass spectrometry. We identified Protein tyrosine phosphatase, receptor type K (Ptprk), Aryl hydrocarbon receptor-interacting protein-like 1 (Aipl1), and Diaphanous related formin 2 (Diaph2) as potential candidates, and established a working model to explain how ZP3 affects GVBD. Finally, we provided preliminary evidence that ZP3 regulates Akt phosphorylation, lamin binding to the nuclear membrane via Aipl1, and organization of the actin cytoskeleton via Diaph2. These findings contribute to our understanding of a novel role played by ZP3 in GVBD.

Supramolecular Polymer-Molecule Complexes as Gain Media for Ultraviolet Lasers.

A novel supramolecular system comprising a complex of 9,9'-diphenyl-9H,9'H-2,2'-bifluorene-9,9'-diol (DPFOH) with poly(methyl methacrylate) (PMMA) is presented as an attractive system for optical gain in the ultraviolet. The analogue compound 9,9'-diphenyl-9H,9'H-2,2'-bifluorene (DPFO8) without an -OH substituent was synthesized alongside DPFOH to confirm the importance of its chemical structure to the thin-film microstructure. A hydrogen-bonding interaction allows the molecule such as DPFOH and a combination of DPFOH and PMMA to have an excellent solution-processed high quality coating film. In stark contrast to the DPFO8 system, we find that the addition of 1 wt % DPFOH to PMMA leads to spontaneous formation of a supramolecular complex via hydrogen bonding interactions, giving rise to a homogeneous film with relatively high photoluminescence quantum efficiency ∼38 (±5)%. The demonstration of ultraviolet laser action with peak wavelength emission at 385 nm provided further evidence of the high optical quality of the DPFOH/PMMA supramolecular complex films. The DPFOH/PMMA supramolecular complex has great potential for use in low-cost solution-processed optoelectronic devices.