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381.
Hammond AL 《Science (New York, N.Y.)》1977,197(4304):623
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Hammond AL 《Science (New York, N.Y.)》1974,184(4134):367-370
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Sidona?Sikorskaite Minna-Liisa?Rajam?kiEmail author Danas?Baniulis Vidmantas?Stanys Jari?PT?Valkonen 《Plant methods》2013,9(1):31
In this study, a protocol is described for rapid preparation of an enriched, reasonably pure fraction of nuclear proteins from the leaves of tobacco (Nicotiana tabacum), potato (Solanum tuberosum) and apple (Malus domestica). The protocol gives reproducible results and can be carried out quickly in 2 hours. Tissue extracts clarified with filtration were treated with non-ionic detergent (Triton X-100) to lyse membranes of contaminating organelles. Nuclei were collected from a 60% Percoll layer of density gradient following low-speed centrifugation. Western blot analysis using antibodies to marker proteins of organelles indicated that the nuclear protein fractions were highly enriched and free or nearly free of proteins from the endoplasmic reticulum and chloroplasts. 相似文献
385.
Hammond GR Fischer MJ Anderson KE Holdich J Koteci A Balla T Irvine RF 《Science (New York, N.Y.)》2012,337(6095):727-730
The quantitatively minor phospholipid phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P(2)] fulfills many cellular functions in the plasma membrane (PM), whereas its synthetic precursor, phosphatidylinositol 4-phosphate (PI4P), has no assigned PM roles apart from PI(4,5)P(2) synthesis. We used a combination of pharmacological and chemical genetic approaches to probe the function of PM PI4P, most of which was not required for the synthesis or functions of PI(4,5)P(2). However, depletion of both lipids was required to prevent PM targeting of proteins that interact with acidic lipids or activation of the transient receptor potential vanilloid 1 cation channel. Therefore, PI4P contributes to the pool of polyanionic lipids that define plasma membrane identity and to some functions previously attributed specifically to PI(4,5)P(2), which may be fulfilled by a more general polyanionic lipid requirement. 相似文献
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Steele A McCubbin FM Fries M Kater L Boctor NZ Fogel ML Conrad PG Glamoclija M Spencer M Morrow AL Hammond MR Zare RN Vicenzi EP Siljeström S Bowden R Herd CD Mysen BO Shirey SB Amundsen HE Treiman AH Bullock ES Jull AJ 《Science (New York, N.Y.)》2012,337(6091):212-215
The source and nature of carbon on Mars have been a subject of intense speculation. We report the results of confocal Raman imaging spectroscopy on 11 martian meteorites, spanning about 4.2 billion years of martian history. Ten of the meteorites contain abiotic macromolecular carbon (MMC) phases detected in association with small oxide grains included within high-temperature minerals. Polycyclic aromatic hydrocarbons were detected along with MMC phases in Dar al Gani 476. The association of organic carbon within magmatic minerals indicates that martian magmas favored precipitation of reduced carbon species during crystallization. The ubiquitous distribution of abiotic organic carbon in martian igneous rocks is important for understanding the martian carbon cycle and has implications for future missions to detect possible past martian life. 相似文献
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