Normal Proliferation and Tumorigenesis but Impaired Pancreatic Function in Mice Lacking the Cell Cycle Regulator Sei1

Sei1 is a positive regulator of proliferation that promotes the assembly of Cdk4-cyclin D complexes and enhances the transcriptional activity of E2f1. The potential oncogenic role of Sei1 is further suggested by its overexpression in various types of human cancers. To study the role of Sei1, we have generated a mouse line deficient for this gene. Sei1-null fibroblasts did not show abnormalities regarding proliferation or susceptibility to neoplastic transformation, nor did we observe defects on Cdk4 complexes or E2f activity. Sei1-null mice were viable, did not present overt pathologies, had a normal lifespan, and had a normal susceptibility to spontaneous and chemically-induced cancer. Pancreatic insulin-producing cells are known to be particularly sensitive to Cdk4-cyclin D and E2f activities, and we have observed that Sei1 is highly expressed in pancreatic islets compared to other tissues. Interestingly, Sei1-null mice present lower number of islets, decreased β-cell area, impaired insulin secretion, and glucose intolerance. These defects were associated to nuclear accumulation of the cell-cycle inhibitors p21Cip1 and p27Kip1 in islet cells. We conclude that Sei1 plays an important role in pancreatic β-cells, which supports a functional link between Sei1 and the core cell cycle regulators specifically in the context of the pancreas

Chia (Salvia hispanica L.) products as ingredients for reformulating frankfurters: Effects on quality properties and shelf-life

Several strategies were examined for incorporating chia products (seeds, flour and a coproduct from cold-press oil extraction) in frankfurters. The nutritional composition, technological properties and sensory attributes of the resulting products were studied in relation to the formulation used and, lipid oxidation, pH, residual nitrite level and microbiological properties were evaluated during chilled storage. Application of these chia products (3%) was seen to enhance the nutritional composition of frankfurters, without adversely affecting the technological properties of the final product. In general, although differences were detected in the sensory attributes of the frankfurters reformulated with chia products (most of them when chia coproduct was added), all of them were judged acceptable. Besides the quality aspects, these reformulation strategies had beneficial effects on some technological properties during chilled storage: better resistance to oxidation (controlling the TBARS increase during storage) and lower residual nitrite levels than control (both effects presumably because the chia polyphenols content) and no effect on microbiological safet

Cocoa coproducts-based and walnut oil gelled emulsion as animal fat replacer and healthy bioactive source in beef burgers

The aim of this work was to evaluate the effects on the chemical, physic-chemical, tech-nological, and sensory properties of beef burger when replacing different quantities of fat (50 and 100%) with different levels of oil-in-water-gelled emulsion elaborated with walnut oil and cocoa bean shell flour (GECW). The chemical composition of the samples was affected by the fat replace-ment. The reformulation increased the moisture and ash content while the fat and protein content decreased with respect to the control sample. The linolenic and linolenic acid content of the beef burgers increased as the GECW replacement was augmented. The polyunsaturated fatty/saturated fatty acid ratio increased in both raw and cooked burgers, whereas the atherogenicity index and thrombogenicity index were reduced in both raw and cooked burgers with respect to the control sample. The use of GECW as a fat replacer was found to be effective in improving the cooking loss. Similarly, there were positive effects on reductions in the diameter and the increases in the thickness of the beef burgers. Regarding lipid stability, in both the raw and cooked burgers, the reformulation increased the 2-thiobarbituric acid reactive substance (TBARs) values with respect to the control sample. In both types of reformulated burgers, three bound polyphenols (mainly catechin and epicatechin) and two free polyphenols were identified, as were methylxanthines theobromine and caffeine. The sensory properties for the control and partial pork backfat replacement treatments were similar, while the sample with the total pork backfat replacement treatment showed the lowest scores. The blend of cocoa bean shell flour and walnut oil could be used as new ingredients for the development of beef burgers with a healthier nutritional profile without demeriting their sensory or cooking characteristics and physic-chemical properties.This research was funded by Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo CYTED: 119RT0568.info:eu-repo/semantics/publishedVersio

Calcium-dependent oligomerization of CAR proteins at cell membrane modulates ABA signaling

[EN] Regulation of ion transport in plants is essential for cell function. Abiotic stress unbalances cell ion homeostasis, and plants tend to readjust it, regulating membrane transporters and channels. The plant hormone abscisic acid (ABA) and the second messenger Ca2+ are central in such processes, as they are involved in the regulation of protein kinases and phosphatases that control ion transport activity in response to environmental stimuli. The identification and characterization of the molecular mechanisms underlying the effect of ABA and Ca2+ signaling pathways on membrane function are central and could provide opportunities for crop improvement. The C2-domain ABA-related (CAR) family of small proteins is involved in the Ca2+-dependent recruitment of the pyrabactin resistance 1/PYR1like (PYR/PYL) ABA receptors to the membrane. However, to fully understand CAR function, it is necessary to define a molecular mechanism that integrates Ca2+ sensing, membrane interaction, and the recognition of the PYR/PYL interacting partners. We present structural and biochemical data showing that CARs are peripheral membrane proteins that functionally cluster on the membrane and generate strong positive membrane curvature in a Ca2+-dependent manner. These features represent a mechanism for the generation, stabilization, and/or specific recognition of membrane discontinuities. Such structures may act as signaling platforms involved in the recruitment of PYR/PYL receptors and other signaling components involved in cell responses to stress.A.A. and J.A.M. thank the European Syncrotron Radiation Facility and EMBL for access to the synchrotron radiation source. This work was funded by Ministerio de Economia y Competitividad (MINECO) Grants BFU2014-59796-R (to A.A.), BFU2011-28184-C02 (to M.J.S.-B.), and BIO2014-52537-R (to P.L.R.) and Comunidad de Madrid Grant S2010/BMD-2457 (to A.A and M.M.). M.J.S.-B. is supported by Ramon y Cajal Contract RYC-2008-03449 from MINECO and M.D. by a fellowship from Senacyt-Ifarhu. Access to the High Throughput Crystallization facility at European Molecular Biology Laboratory (EMBL) Grenoble was supported by the European Community's Seventh Framework Programme through the Protein Production Platform project (P-CUBE) Grant 227764.Diaz, M.; Sanchez-Barrena, MJ.; Gonzalez Rubio, JM.; Rodríguez Solovey, LN.; Fernández, D.; Antoni-Alandes, R.; Yunta, C.... (2016). Calcium-dependent oligomerization of CAR proteins at cell membrane modulates ABA signaling. Proceedings of the National Academy of Sciences. 113(3):E396-E405. https://doi.org/10.1073/pnas.1512779113SE396E4051133Serrano, R., & Rodriguez-Navarro, A. (2001). Ion homeostasis during salt stress in plants. Current Opinion in Cell Biology, 13(4), 399-404. doi:10.1016/s0955-0674(00)00227-1Bassil, E., & Blumwald, E. (2014). The ins and outs of intracellular ion homeostasis: NHX-type cation/H + transporters. Current Opinion in Plant Biology, 22, 1-6. doi:10.1016/j.pbi.2014.08.002Batistič, O., & Kudla, J. (2012). Analysis of calcium signaling pathways in plants. Biochimica et Biophysica Acta (BBA) - General Subjects, 1820(8), 1283-1293. doi:10.1016/j.bbagen.2011.10.012Cutler, S. R., Rodriguez, P. L., Finkelstein, R. R., & Abrams, S. R. (2010). Abscisic Acid: Emergence of a Core Signaling Network. Annual Review of Plant Biology, 61(1), 651-679. doi:10.1146/annurev-arplant-042809-112122McAinsh, M. R., Brownlee, C., & Hetherington, A. M. (1990). Abscisic acid-induced elevation of guard cell cytosolic Ca2+ precedes stomatal closure. Nature, 343(6254), 186-188. doi:10.1038/343186a0Maierhofer, T., Diekmann, M., Offenborn, J. N., Lind, C., Bauer, H., Hashimoto, K., … Hedrich, R. (2014). Site- and kinase-specific phosphorylation-mediated activation of SLAC1, a guard cell anion channel stimulated by abscisic acid. Science Signaling, 7(342), ra86-ra86. doi:10.1126/scisignal.2005703Allen, G. J., Kwak, J. M., Chu, S. P., Llopis, J., Tsien, R. Y., Harper, J. F., & Schroeder, J. I. (1999). Cameleon calcium indicator reports cytoplasmic calcium dynamics in Arabidopsis guard cells. The Plant Journal, 19(6), 735-747. doi:10.1046/j.1365-313x.1999.00574.xLee, S. C., Lan, W.-Z., Kim, B.-G., Li, L., Cheong, Y. H., Pandey, G. K., … Luan, S. (2007). A protein phosphorylation/dephosphorylation network regulates a plant potassium channel. Proceedings of the National Academy of Sciences, 104(40), 15959-15964. doi:10.1073/pnas.0707912104Sánchez-Barrena, M., Martínez-Ripoll, M., & Albert, A. (2013). Structural Biology of a Major Signaling Network that Regulates Plant Abiotic Stress: The CBL-CIPK Mediated Pathway. International Journal of Molecular Sciences, 14(3), 5734-5749. doi:10.3390/ijms14035734Quan, R., Lin, H., Mendoza, I., Zhang, Y., Cao, W., Yang, Y., … Guo, Y. (2007). SCABP8/CBL10, a Putative Calcium Sensor, Interacts with the Protein Kinase SOS2 to Protect Arabidopsis Shoots from Salt Stress. The Plant Cell, 19(4), 1415-1431. doi:10.1105/tpc.106.042291Ma, Y., Szostkiewicz, I., Korte, A., Moes, D., Yang, Y., Christmann, A., & Grill, E. (2009). Regulators of PP2C Phosphatase Activity Function as Abscisic Acid Sensors. Science. doi:10.1126/science.1172408Park, S.-Y., Fung, P., Nishimura, N., Jensen, D. R., Fujii, H., Zhao, Y., … Cutler, S. R. (2009). Abscisic Acid Inhibits Type 2C Protein Phosphatases via the PYR/PYL Family of START Proteins. Science. doi:10.1126/science.1173041Santiago, J., Rodrigues, A., Saez, A., Rubio, S., Antoni, R., Dupeux, F., … Rodriguez, P. L. (2009). Modulation of drought resistance by the abscisic acid receptor PYL5 through inhibition of clade A PP2Cs. The Plant Journal, 60(4), 575-588. doi:10.1111/j.1365-313x.2009.03981.xNishimura, N., Sarkeshik, A., Nito, K., Park, S.-Y., Wang, A., Carvalho, P. C., … Schroeder, J. I. (2009). PYR/PYL/RCAR family members are major in-vivo ABI1 protein phosphatase 2C-interacting proteins in Arabidopsis. The Plant Journal, 61(2), 290-299. doi:10.1111/j.1365-313x.2009.04054.xWang, P., Xue, L., Batelli, G., Lee, S., Hou, Y.-J., Van Oosten, M. J., … Zhu, J.-K. (2013). Quantitative phosphoproteomics identifies SnRK2 protein kinase substrates and reveals the effectors of abscisic acid action. Proceedings of the National Academy of Sciences, 110(27), 11205-11210. doi:10.1073/pnas.1308974110Umezawa, T., Sugiyama, N., Takahashi, F., Anderson, J. C., Ishihama, Y., Peck, S. C., & Shinozaki, K. (2013). Genetics and Phosphoproteomics Reveal a Protein Phosphorylation Network in the Abscisic Acid Signaling Pathway in Arabidopsis thaliana. Science Signaling, 6(270), rs8-rs8. doi:10.1126/scisignal.2003509Kollist, H., Nuhkat, M., & Roelfsema, M. R. G. (2014). Closing gaps: linking elements that control stomatal movement. New Phytologist, 203(1), 44-62. doi:10.1111/nph.12832Lind, C., Dreyer, I., López-Sanjurjo, E. J., von Meyer, K., Ishizaki, K., Kohchi, T., … Hedrich, R. (2015). Stomatal Guard Cells Co-opted an Ancient ABA-Dependent Desiccation Survival System to Regulate Stomatal Closure. Current Biology, 25(7), 928-935. doi:10.1016/j.cub.2015.01.067Geiger, D., Scherzer, S., Mumm, P., Stange, A., Marten, I., Bauer, H., … Hedrich, R. (2009). Activity of guard cell anion channel SLAC1 is controlled by drought-stress signaling kinase-phosphatase pair. Proceedings of the National Academy of Sciences, 106(50), 21425-21430. doi:10.1073/pnas.0912021106Imes, D., Mumm, P., Böhm, J., Al-Rasheid, K. A. S., Marten, I., Geiger, D., & Hedrich, R. (2013). Open stomata 1 (OST1) kinase controls R-type anion channel QUAC1 in Arabidopsis guard cells. The Plant Journal, 74(3), 372-382. doi:10.1111/tpj.12133Ishitani, M., Liu, J., Halfter, U., Kim, C.-S., Shi, W., & Zhu, J.-K. (2000). SOS3 Function in Plant Salt Tolerance Requires N-Myristoylation and Calcium Binding. The Plant Cell, 12(9), 1667-1677. doi:10.1105/tpc.12.9.1667Grefen, C., & Blatt, M. R. (2012). Do Calcineurin B-Like Proteins Interact Independently of the Serine Threonine Kinase CIPK23 with the K+ Channel AKT1? Lessons Learned from a Ménage à Trois. Plant Physiology, 159(3), 915-919. doi:10.1104/pp.112.198051Qiu, Q.-S., Guo, Y., Dietrich, M. A., Schumaker, K. S., & Zhu, J.-K. (2002). Regulation of SOS1, a plasma membrane Na+/H+ exchanger in Arabidopsis thaliana, by SOS2 and SOS3. Proceedings of the National Academy of Sciences, 99(12), 8436-8441. doi:10.1073/pnas.122224699Quintero, F. J., Martinez-Atienza, J., Villalta, I., Jiang, X., Kim, W.-Y., Ali, Z., … Pardo, J. M. (2011). Activation of the plasma membrane Na/H antiporter Salt-Overly-Sensitive 1 (SOS1) by phosphorylation of an auto-inhibitory C-terminal domain. Proceedings of the National Academy of Sciences, 108(6), 2611-2616. doi:10.1073/pnas.1018921108Núñez-Ramírez, R., Sánchez-Barrena, M. J., Villalta, I., Vega, J. F., Pardo, J. M., Quintero, F. J., … Albert, A. (2012). Structural Insights on the Plant Salt-Overly-Sensitive 1 (SOS1) Na+/H+ Antiporter. Journal of Molecular Biology, 424(5), 283-294. doi:10.1016/j.jmb.2012.09.015Ohta, M., Guo, Y., Halfter, U., & Zhu, J.-K. (2003). A novel domain in the protein kinase SOS2 mediates interaction with the protein phosphatase 2C ABI2. Proceedings of the National Academy of Sciences, 100(20), 11771-11776. doi:10.1073/pnas.2034853100Xu, J., Li, H.-D., Chen, L.-Q., Wang, Y., Liu, L.-L., He, L., & Wu, W.-H. (2006). A Protein Kinase, Interacting with Two Calcineurin B-like Proteins, Regulates K+ Transporter AKT1 in Arabidopsis. Cell, 125(7), 1347-1360. doi:10.1016/j.cell.2006.06.011Geiger, D., Scherzer, S., Mumm, P., Marten, I., Ache, P., Matschi, S., … Hedrich, R. (2010). Guard cell anion channel SLAC1 is regulated by CDPK protein kinases with distinct Ca2+affinities. Proceedings of the National Academy of Sciences, 107(17), 8023-8028. doi:10.1073/pnas.0912030107Brandt, B., Brodsky, D. E., Xue, S., Negi, J., Iba, K., Kangasjarvi, J., … Schroeder, J. I. (2012). Reconstitution of abscisic acid activation of SLAC1 anion channel by CPK6 and OST1 kinases and branched ABI1 PP2C phosphatase action. Proceedings of the National Academy of Sciences, 109(26), 10593-10598. doi:10.1073/pnas.1116590109Rodriguez, L., Gonzalez-Guzman, M., Diaz, M., Rodrigues, A., Izquierdo-Garcia, A. C., Peirats-Llobet, M., … Rodriguez, P. L. (2014). C2-Domain Abscisic Acid-Related Proteins Mediate the Interaction of PYR/PYL/RCAR Abscisic Acid Receptors with the Plasma Membrane and Regulate Abscisic Acid Sensitivity in Arabidopsis. The Plant Cell, 26(12), 4802-4820. doi:10.1105/tpc.114.129973Martens, S., & McMahon, H. T. (2008). Mechanisms of membrane fusion: disparate players and common principles. Nature Reviews Molecular Cell Biology, 9(7), 543-556. doi:10.1038/nrm2417Martens, S., Kozlov, M. M., & McMahon, H. T. (2007). How Synaptotagmin Promotes Membrane Fusion. Science, 316(5828), 1205-1208. doi:10.1126/science.1142614Jahn, R., Lang, T., & Südhof, T. C. (2003). Membrane Fusion. Cell, 112(4), 519-533. doi:10.1016/s0092-8674(03)00112-0Sutter, J.-U., Sieben, C., Hartel, A., Eisenach, C., Thiel, G., & Blatt, M. R. (2007). Abscisic Acid Triggers the Endocytosis of the Arabidopsis KAT1 K+ Channel and Its Recycling to the Plasma Membrane. Current Biology, 17(16), 1396-1402. doi:10.1016/j.cub.2007.07.020Bueso, E., Rodriguez, L., Lorenzo-Orts, L., Gonzalez-Guzman, M., Sayas, E., Muñoz-Bertomeu, J., … Rodriguez, P. L. (2014). The single-subunit RING-type E3 ubiquitin ligase RSL1 targets PYL4 and PYR1 ABA receptors in plasma membrane to modulate abscisic acid signaling. The Plant Journal, 80(6), 1057-1071. doi:10.1111/tpj.12708Larsen, J. B., Jensen, M. B., Bhatia, V. K., Pedersen, S. L., Bjørnholm, T., Iversen, L., … Stamou, D. (2015). Membrane curvature enables N-Ras lipid anchor sorting to liquid-ordered membrane phases. Nature Chemical Biology, 11(3), 192-194. doi:10.1038/nchembio.1733Demir, F., Horntrich, C., Blachutzik, J. O., Scherzer, S., Reinders, Y., Kierszniowska, S., … Kreuzer, I. (2013). Arabidopsis nanodomain-delimited ABA signaling pathway regulates the anion channel SLAH3. Proceedings of the National Academy of Sciences, 110(20), 8296-8301. doi:10.1073/pnas.1211667110Guerrero-Valero, M., Ferrer-Orta, C., Querol-Audi, J., Marin-Vicente, C., Fita, I., Gomez-Fernandez, J. C., … Corbalan-Garcia, S. (2009). Structural and mechanistic insights into the association of PKC -C2 domain to PtdIns(4,5)P2. Proceedings of the National Academy of Sciences, 106(16), 6603-6607. doi:10.1073/pnas.0813099106Guillen, J., Ferrer-Orta, C., Buxaderas, M., Perez-Sanchez, D., Guerrero-Valero, M., Luengo-Gil, G., … Corbalan-Garcia, S. (2013). Structural insights into the Ca2+ and PI(4,5)P2 binding modes of the C2 domains of rabphilin 3A and synaptotagmin 1. Proceedings of the National Academy of Sciences, 110(51), 20503-20508. doi:10.1073/pnas.1316179110Corbalan-Garcia, S., & Gómez-Fernández, J. C. (2014). Signaling through C2 domains: More than one lipid target. Biochimica et Biophysica Acta (BBA) - Biomembranes, 1838(6), 1536-1547. doi:10.1016/j.bbamem.2014.01.008CHO, W., & STAHELIN, R. (2006). Membrane binding and subcellular targeting of C2 domains. Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids, 1761(8), 838-849. doi:10.1016/j.bbalip.2006.06.014Verdaguer, N., Corbalan-Garcia, S., Ochoa, W. F., Fita, I., & Gómez-Fernández, J. C. (1999). Ca2+ bridges the C2 membrane-binding domain of protein kinase Cα directly to phosphatidylserine. The EMBO Journal, 18(22), 6329-6338. doi:10.1093/emboj/18.22.6329Honigmann, A., van den Bogaart, G., Iraheta, E., Risselada, H. J., Milovanovic, D., Mueller, V., … Jahn, R. (2013). Phosphatidylinositol 4,5-bisphosphate clusters act as molecular beacons for vesicle recruitment. Nature Structural & Molecular Biology, 20(6), 679-686. doi:10.1038/nsmb.2570Ausili, A., Corbalán-García, S., Gómez-Fernández, J. C., & Marsh, D. (2011). Membrane docking of the C2 domain from protein kinase Cα as seen by polarized ATR-IR. The role of PIP2. Biochimica et Biophysica Acta (BBA) - Biomembranes, 1808(3), 684-695. doi:10.1016/j.bbamem.2010.11.035Hermoso, J. A., Lagartera, L., González, A., Stelter, M., García, P., Martínez-Ripoll, M., … Menéndez, M. (2005). Insights into pneumococcal pathogenesis from the crystal structure of the modular teichoic acid phosphorylcholine esterase Pce. Nature Structural & Molecular Biology, 12(6), 533-538. doi:10.1038/nsmb940Thompson, D., Pepys, M. B., & Wood, S. P. (1999). The physiological structure of human C-reactive protein and its complex with phosphocholine. Structure, 7(2), 169-177. doi:10.1016/s0969-2126(99)80023-9Ochoa, W. F., Garcia-Garcia, J., Fita, I., Corbalan-Garcia, S., Verdaguer, N., & Gomez-Fernandez, J. C. (2001). Structure of the C2 domain from novel protein kinase Cϵ. A membrane binding model for Ca2+-independent C2 domains. Journal of Molecular Biology, 311(4), 837-849. doi:10.1006/jmbi.2001.4910Fuson, K., Rice, A., Mahling, R., Snow, A., Nayak, K., Shanbhogue, P., … Sutton, R. B. (2014). Alternate Splicing of Dysferlin C2A Confers Ca2+-Dependent and Ca2+-Independent Binding for Membrane Repair. Structure, 22(1), 104-115. doi:10.1016/j.str.2013.10.001Radhakrishnan, A., Stein, A., Jahn, R., & Fasshauer, D. (2009). The Ca2+Affinity of Synaptotagmin 1 Is Markedly Increased by a Specific Interaction of Its C2B Domain with Phosphatidylinositol 4,5-Bisphosphate. Journal of Biological Chemistry, 284(38), 25749-25760. doi:10.1074/jbc.m109.042499Schapire, A. L., Voigt, B., Jasik, J., Rosado, A., Lopez-Cobollo, R., Menzel, D., … Botella, M. A. (2008). Arabidopsis Synaptotagmin 1 Is Required for the Maintenance of Plasma Membrane Integrity and Cell Viability. The Plant Cell, 20(12), 3374-3388. doi:10.1105/tpc.108.063859Wang, J., Bello, O., Auclair, S. M., Wang, J., Coleman, J., Pincet, F., … Rothman, J. E. (2014). Calcium sensitive ring-like oligomers formed by synaptotagmin. Proceedings of the National Academy of Sciences, 111(38), 13966-13971. doi:10.1073/pnas.1415849111Jaenicke, R., & Rudolph, R. (1986). [12]Refolding and association of oligomeric proteins. Enzyme Structure Part L, 218-250. doi:10.1016/0076-6879(86)31043-7Goni, G. M., Epifano, C., Boskovic, J., Camacho-Artacho, M., Zhou, J., Bronowska, A., … Lietha, D. (2014). Phosphatidylinositol 4,5-bisphosphate triggers activation of focal adhesion kinase by inducing clustering and conformational changes. Proceedings of the National Academy of Sciences, 111(31), E3177-E3186. doi:10.1073/pnas.1317022111Wilkie, A. O. (1994). The molecular basis of genetic dominance. Journal of Medical Genetics, 31(2), 89-98. doi:10.1136/jmg.31.2.89Saez, A., Apostolova, N., Gonzalez-Guzman, M., Gonzalez-Garcia, M. P., Nicolas, C., Lorenzo, O., & Rodriguez, P. L. (2003). Gain-of-function and loss-of-function phenotypes of the protein phosphatase 2CHAB1reveal its role as a negative regulator of abscisic acid signalling. The Plant Journal, 37(3), 354-369. doi:10.1046/j.1365-313x.2003.01966.xSimons, K., & Gerl, M. J. (2010). Revitalizing membrane rafts: new tools and insights. Nature Reviews Molecular Cell Biology, 11(10), 688-699. doi:10.1038/nrm2977McMahon, H. T., & Boucrot, E. (2015). Membrane curvature at a glance. Journal of Cell Science, 128(6), 1065-1070. doi:10.1242/jcs.114454Tapken, W., & Murphy, A. S. (2015). Membrane nanodomains in plants: capturing form, function, and movement. Journal of Experimental Botany, 66(6), 1573-1586. doi:10.1093/jxb/erv054Lingwood, D., & Simons, K. (2007). Detergent resistance as a tool in membrane research. Nature Protocols, 2(9), 2159-2165. doi:10.1038/nprot.2007.294Schuck, P. (2000). Size-Distribution Analysis of Macromolecules by Sedimentation Velocity Ultracentrifugation and Lamm Equation Modeling. Biophysical Journal, 78(3), 1606-1619. doi:10.1016/s0006-3495(00)76713-0Bensmihen, S., To, A., Lambert, G., Kroj, T., Giraudat, J., & Parcy, F. (2004). Analysis of an activated ABI5 allele using a new selection method for transgenic Arabidopsis seeds. FEBS Letters, 561(1-3), 127-131. doi:10.1016/s0014-5793(04)00148-6Deblaere, R., Bytebier, B., De Greve, H., Deboeck, F., Schell, J., Van Montagu, M., & Leemans, J. (1985). Efficient octopine Ti plasmid-derived vectors forAgrobacterium-mediated gene transfer to plants. Nucleic Acids Research, 13(13), 4777-4788. doi:10.1093/nar/13.13.4777Clough, S. J., & Bent, A. F. (1998). Floral dip: a simplified method forAgrobacterium-mediated transformation ofArabidopsis thaliana. The Plant Journal, 16(6), 735-743. doi:10.1046/j.1365-313x.1998.00343.xHua, J. (2001). Plant growth homeostasis is controlled by the Arabidopsis BON1 and BAP1 genes. Genes & Development, 15(17), 2263-2272. doi:10.1101/gad.918101Kabsch, W. (2010). XDS. Acta Crystallographica Section D Biological Crystallography, 66(2), 125-132. doi:10.1107/s0907444909047337Winn, M. D., Ballard, C. C., Cowtan, K. D., Dodson, E. J., Emsley, P., Evans, P. R., … Wilson, K. S. (2011). Overview of theCCP4 suite and current developments. Acta Crystallographica Section D Biological Crystallography, 67(4), 235-242. doi:10.1107/s0907444910045749Adams, P. D., Afonine, P. V., Bunkóczi, G., Chen, V. B., Davis, I. W., Echols, N., … Zwart, P. H. (2010). PHENIX: a comprehensive Python-based system for macromolecular structure solution. Acta Crystallographica Section D Biological Crystallography, 66(2), 213-221. doi:10.1107/s0907444909052925Emsley, P., & Cowtan, K. (2004). Coot: model-building tools for molecular graphics. Acta Crystallographica Section D Biological Crystallography, 60(12), 2126-2132. doi:10.1107/s0907444904019158Dimasi, N., Flot, D., Dupeux, F., & Márquez, J. A. (2007). Expression, crystallization and X-ray data collection from microcrystals of the extracellular domain of the human inhibitory receptor expressed on myeloid cells IREM-1. Acta Crystallographica Section F Structural Biology and Crystallization Communications, 63(3), 204-208. doi:10.1107/s1744309107004903Emsley, P., Lohkamp, B., Scott, W. G., & Cowtan, K. (2010). Features and development ofCoot. Acta Crystallographica Section D Biological Crystallography, 66(4), 486-501. doi:10.1107/s0907444910007493DeLano (2002) The PyMOL Molecular Graphics System, 1.5.0.4 (DeLano Scientific, San Carlos, CA

A mutation in the POT1 gene is responsible for cardiac angiosarcoma in TP53-negative Li-Fraumeni-like families

Cardiac angiosarcoma (CAS) is a rare malignant tumour whose genetic basis is unknown. Here we show, by whole-exome sequencing of a TP53-negative Li-Fraumeni-like (LFL) family including CAS cases, that a missense variant (p.R117C) in POT1 (protection of telomeres 1) gene is responsible for CAS. The same gene alteration is found in two other LFL families with CAS, supporting the causal effect of the identified mutation. We extend the analysis to TP53-negative LFL families with no CAS and find the same mutation in a breast AS family. The mutation is recently found once in 121,324 studied alleles in ExAC server but it is not described in any other database or found in 1,520 Spanish controls. In silico structural analysis suggests how the mutation disrupts POT1 structure. Functional and in vitro studies demonstrate that carriers of the mutation show reduced telomere-bound POT1 levels, abnormally long telomeres and increased telomere fragility

Ciencias de la Biología y Agronomía

Este volumen I contiene 17 capítulos arbitrados que se ocupan de estos asuntos en Tópicos Selectos de Ciencias de la Biología y Agronomía, elegidos de entre las contribuciones, reunimos algunos investigadores y estudiantes. Se presenta un Estudio Comparativo de los Recursos Hidrológico-Forestales de la Microcuenca de la Laguna de Epatlan, Pue. (1993 a 2014); la Situación Actual de la Mancha de Asfalto en Maíz (Zea mays L.) en los Municipios de Jiquipilas y Ocozocoautla, Chiapas, México; las poblaciones sobresalientes de maíz de la raza Zapalote Chico, en la Región Istmeña de Oaxaca; Se indica el índice de área foliar de cultivo de Chile Poblano mediante dos métodos en condiciones protegidas; Esquivel, Urzúa y Ramírez exploran el efecto de la biofertilización con Azospirillum en el crecimiento y producción de Jitomate; esbozan su artículo sobre la determinación del nivel de Heterosis en híbridos de Maíz para la Comarca Lagunera; una investigación sobre la estabilización de semilla de Solanum lycopersicum durante el almacenamiento y estimulación de la germinación; acotan sobre el CTAB como una nueva opción para la detección de Huanglongbing en cítricos, plantean su evaluación sobre el aluminio y cómo afecta la vida de florero de Heliconia psittacorum; indican sobre el impacto del H-564C, como un híbrido de maíz con alta calidad de proteina para el trópico húmedo de México; presetan su investigación sobre la producción de Piña Cayena Lisa y MD2 (Ananas comosus L.) en condiciones de Loma Bonita, en Oaxaca; acotan sobre el efecto de coberteras como control biológico por conservación contra áfidos en Nogal Pecanero; esbozan sobre la caracterización de cuatro genotipos de Frijol Negro en Martínez de la Torre, Veracruz, México; presentan una caracterización hidroecológica de la microcuenca de Arroyo Prieto, Yuriría, Gto., y alternativas para su restauración ambiental; presentan su investigación sobre el efecto del hongo Beauveria bassiana sobre solubilización de fosfatos y la disponibilidad de fósforo en el suelo; plantean su investigación sobre la Germinación y regeneración in vitro de Epidendrum falcatum LINDL; esbozan su artículo sobre genotipos de frijol negro y su tolerancia a sequía terminal en Veracruz, México

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Trabectedin and Campthotecin Synergistically Eliminate Cancer Stem Cells in Cell-of-Origin Sarcoma Models

Trabectedin has been approved for second-line treatment of soft tissue sarcomas. However, its efficacy to target sarcoma initiating cells has not been addressed yet. Here, we used pioneer models of myxoid/round cell liposarcoma (MRCLS) and undifferentiated pleomorphic sarcoma (UPS) developed from transformed human mesenchymal stromal/stem cells (MSCs) to evaluate the effect of trabectedin in the cell type responsible for initiating sarcomagenesis and their derived cancer stem cells (CSC) subpopulations. We found that low nanomolar concentrations of trabectedin efficiently inhibited the growth of sarcoma-initiating cells, induced cell cycle arrest, DNA damage and apoptosis. Interestingly, trabectedin treatment repressed the expression of multiple genes responsible for the development of the CSC phenotype, including pluripotency factors, CSC markers and related signaling pathways. Accordingly, trabectedin induced apoptosis and reduced the survival of CSC-enriched tumorsphere cultures with the same efficiency that inhibits the growth of bulk tumor population. In vivo, trabectedin significantly reduced the mitotic index of MRCLS xenografts and inhibited tumor growth at a similar extent to that observed in doxorubicin-treated tumors. Combination of trabectedin with campthotecin (CPT), a chemotherapeutic drug that shows a robust anti-tumor activity when combined with alkylating agents, resulted in a very strong synergistic inhibition of tumor cell growth and highly increased DNA damage and apoptosis induction. Importantly, the enhanced anti-tumor activity of this combination was also observed in CSC subpopulations. These data suggest that trabectedin and CPT combination may constitute a novel strategy to effectively target both the cell-of-origin and CSC subpopulations in sarcoma

Morphological changes, peptidase activity, and effects of exogenous enzymes in the early ontogeny of Nile tilapia, Oreochromis niloticus

During the early ontogeny, the transition from endogenous (yolk protein) to exogenous feeding (artificial diets) represents a critical period linked to the undifferentiated digestive system, with low digestibility of food protein. The objectives of this work were to characterize the morphology of the early Nile tilapia (Oreochromis niloticus) developmental stages and determine the activity of alkaline and acid peptidase enzymes during the ontogenesis from hatching to 20 days post-hatching (DPH). Also, the in vitro effect that exogenous enzymes from Argentine red shrimp (Pleoticus muelleri) waste have on the alkaline peptidases of larvae from 6 to 20 DPH (which correspond to the age at which fish eat exogenous food) was studied. Both acid and alkaline peptidase activities varied throughout early ontogeny development (from 0.1 to 1, and from 0.1 to 7.1 UE mg protein−1, respectively). The patterns of both enzyme activity variation would be related with changes in endogenous, mixed and exogenous feeding. Our studies show that the additions of the enzyme extract of shrimp have a synergistic effect (from 3 to 6 times) on endogenous in vitro activity. Moreover, the zymogram analysis demonstrates that the bands corresponding to the activity of each species (tilapia and red shrimp) remain active when they are mixed. The increase in peptidase digestive capacity by addition of exogenous enzymes would maximize the assimilation of nutrients from artificial food during early development.Fil: del Valle, Juana Cristina. Universidad Nacional de Mar del Plata; ArgentinaFil: Zanazzi, Aldo Nahuel. Universidad Tecnológica Nacional; ArgentinaFil: Rodriguez, Yamila Eliana. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Haran, Nora Selma. Universidad Nacional de Mar del Plata; ArgentinaFil: Laitano, Marìa Victoria. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Mallo, Juan Carlos. Universidad Nacional de Mar del Plata; Argentina. Universidad Tecnológica Nacional; ArgentinaFil: Fernandez Gimenez, Analia Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentin