The Xenopus tadpole is able to regenerate its tail, including skin, muscle, notochord, spinal cord and neurons and blood vessels. This process requires rapid tissue growth and morphogenesis. Here we show that a focus of apoptotic cells appears in the regeneration bud within 12 h of amputation. Surprisingly, when caspase-3 activity is specifically inhibited, regeneration is abolished. This is true of tails both before and after the refractory period. Programmed cell death is only required during the first 24 h after amputation, as later inhibition has no effect on regeneration. Inhibition of caspase-dependent apoptosis results in a failure to induce proliferation in the growth zone, a mispatterning of axons in the regenerate, and the appearance of ectopic otoliths in the neural tube, in the context of otherwise normal continued development of the larva. Larvae amputated during the refractory stage exhibit a much broader domain of caspase-3-positive cells, suggesting a window for the amount of apoptosis that is compatible with normal regeneration. These data reveal novel roles for apoptosis in development and indicate that a degree of apoptosis is an early and obligate component of normal tail regeneration, suggesting the possibility of the existence of endogenous inhibitory cells that must be destroyed by programmed cell death for regeneration to occur.

Consistent laterality is a fascinating problem, and study of the Xenopus embryo has led to molecular characterization of extremely early steps in left-right patterning: bioelectrical signals produced by ion pumps functioning upstream of asymmetric gene expression. Here, we reveal a number of novel aspects of the H+/K+-ATPase module in chick and frog embryos. Maternal H+/K+-ATPase subunits are asymmetrically localized along the left-right, dorso-ventral, and animal-vegetal axes during the first cleavage stages, in a process dependent on cytoskeletal organization. Using a reporter domain fused to molecular motors, we show that the cytoskeleton of the early frog embryo can provide asymmetric, directional information for subcellular transport along all three axes. Moreover, we show that the Kir4.1 potassium channel, while symmetrically expressed in a dynamic fashion during early cleavages, is required for normal LR asymmetry of frog embryos. Thus, Kir4.1 is an ideal candidate for the K+ ion exit path needed to allow the electroneutral H+/K+-ATPase to generate voltage gradients. In the chick embryo, we show that H+/K+-ATPase and Kir4.1 are expressed in the primitive streak, and that the known requirement for H+/K+-ATPase function in chick asymmetry does not function through effects on the circumferential expression pattern of Connexin43. These data provide details crucial for the mechanistic modeling of the physiological events linking subcellular processes to large-scale patterning and suggest a model where the early cytoskeleton sets up asymmetric ion flux along the left-right axis as a system of planar polarity functioning orthogonal to the apical-basal polarity of the early blastomeres.

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Two novel reddish-orange alkaloids, mycoleptodiscin A (1) and mycoleptodiscin B (2), were isolated from liquid cultures of the endophytic fungus Mycoleptodiscus sp. that had been isolated from Desmotes incomparabilis in Panama. Elucidation of their structures was accomplished using 1D and 2D NMR spectroscopy in combination with IR spectroscopic and MS data. These compounds are indole-terpenes with a new skeleton uncommon in nature. Mycoleptodiscin B (2) was active in inhibiting the growth of cancer cell lines with IC50 values in the range 0.60-0.78 μM.

Four new compounds, (−)-petrosynoic acids A–D (1–4), and five known congeners, pellynols A (5), C (6), D (7), F (8), and I (9) were isolated from a Petrosia sp. marine sponge collected in American Samoa. Isolation work was guided by cytotoxicity against human lung cancer cells (H460). The structures of the C31-C33 polyacetylenes (1–9) were determined on the basis of 1D- and 2D-NMR analysis, mass spectrometry, and comparison of specific rotation values. Compounds 1–9 were found to be broadly cytotoxic with limited selectivity for cancer cells as they were all moderately active against the A2058 (melanoma), H522-T1 (lung), and H460 (lung) human cancer cell lines as well as IMR-90 quiescent human fibroblast cells.

Objective: Under the background of changing government functions, this paper makes an in-depth study on the standardization construction of public service for national fitness, so as to promote its standardized development, so as to meet the needs of the masses for public service of national fitness. Method: This study uses the methods of literature review, questionnaire survey and mathematical statistics. A total of 787 community residents aged 15-70 were randomly selected in Taizhou city of Jiangsu Province in November 2019. Result: 1) The overall satisfaction rate of residents to the public service of national construction is 54.4%, and has the characteristics of age, education and occupation. 2) According to the survey on the satisfaction of the contents related to national fitness, the residents' satisfaction with the number, types, convenience and opening hours of the national fitness venues and facilities is 51.21%, 48.43%, 50.53% and 54.35%, respectively. However, they are not satisfied with the fees, maintenance and renewal of the facilities, the organization, guidance and consultation of national fitness activities 35%, 43.17%, 36.29%, 43.68% and 43.29%. 3) Through the analysis of the influencing factors of satisfaction with the construction of public service standardization for national fitness, the main reasons for residents' dissatisfaction with the standardization construction of national fitness public service are less participation channels (OR = 2.169, P = 0.021), unconnected with residents' needs (OR = 2.199, P = 0.018), low participation of residents (OR = 3.244, P = 0.002) and lack of standardized talents (OR = 2.769, P = 0.004).

The schweinfurthin class of natural compounds showed selective and potent anti-proliferative activities in the NCI-60 cancer cell panel1,2). Recent work by Burgett et al3) suggested that schweinfurthins may bind to oxysterol-binding protein-related proteins (ORPs) for their anti-proliferative activity. However, the mechanism of the selectivity and potency is still unknown. Here we show that schweinfurthins preferentially inhibited cell proliferation of PTEN-deficient cancer cells across different cancer types, and specifically inhibited AKT phosphorylation in both PTEN wild-type and mutant cancer cells. Intracellularly, a fluorescent schweinfurthin probe localized within the endosome/lysosome structure. Treatment of cells with active schweinfurthins caused fragmentation of the trans-Golgi-network (TGN), a vesicular trafficking system, in a dose- and time-dependent manner, without impacting the cis, med or trans-Golgi matrix structures. An inactive trimethylated analog of schweinfurthins did not display this activity. Using biotinylated probes, we found that schweinfurthins bind to the sterol-binding domain of ORPs; the capacity of binding to ORPs was positively correlated with both TGN fragmentation activity and anti-proliferative activity. These results are consistent with the recent observation that knockdown of specific ORP proteins leads to TGN trafficking disruption4). The fragmentation of TGN by schweinfurthins resulted in specific inhibition of mTOR-AKT pathway signaling in two ways: 1) disruption of lipid raft organization at the plasma membrane, evidenced by diminished trafficking of ceramide, GM1 and sphingomyelin, which inhibited PDK1 phosphorylation; and 2) dislocation of mTOR from its active sites at endosomes and/or lysosomes. Furthermore, we found that PTEN-deficient DLBCL cancer cells were highly sensitive to schweinfurthin treatment in vitro (IC50 values < 10 nM). Normal human fibroblasts were 1000 times less sensitive than the DLBCL cells. Taken together, our results disclosed an important role of the TGN, which was specifically targeted by schweinfurthins, in mTOR-AKT signaling and in cancer cell survival, suggesting that analogs of schweinfurthin might offer promising novel therapeutics for treating mTOR-AKT signaling-addicted cancer cells such as PTEN-deficient DLBCL. 1. Beutler JA, et al. Cytotoxic geranyl stilbenes from Macaranga schweinfurthii. J Nat Prod., 1998, 61:1509-1512. 2. Yoder BJ, et al. Antiproliferative prenylated stilbenes and flavonoids from Macaranga alnifolia from the Madagascar rainforest. J Nat Prod., 2007, 70:342-346. 3. Burgett AW, et al. Natural products reveal cancer cell dependence on oxysterol-binding proteins. Nat Chem Biol., 2011, 7:639-647. 4. Du X, et al. A role for oxysterol-binding protein-related protein 5 in endosomal cholesterol trafficking. J Cell Biol., 2011, 192:121-135. Citation Format: Xingfeng Bao, Naoko Hata, Kishan Agarwala, Zichun Wang, Winnie Lee, Lana Parent, Hongsheng Cheng, Dayong Qiu, Yongchun Shen, Bingfan Du, Wanjun Zheng, Nanding Zhao, Maarten Postema, Mary Woodall Jappe, Yasutaka Takase, Toshimitsu Uenaka, Kenichi Nomoto. Antiproliferative schweinfurthins reveal a role of the trans-Golgi-network in mTOR-AKT signaling and cancer cell survival. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2788. doi:10.1158/1538-7445.AM2014-2788