Necrotic Cells Actively Attract Phagocytes through the Collaborative Action of Two Distinct PS-Exposure Mechanisms
Necrosis is a type of cell death often caused by cell injury and is linked to human diseases including neuron degeneration, stroke, and cancer. Necrotic cells undergo distinct morphological changes, including swelling, before being engulfed and degraded by engulfing cells. The clearance of necrotic cells from animal bodies is important for wound healing and for preventing harmful inflammatory and autoimmune responses. However, the mechanisms by which necrotic cells are removed remain elusive. We study the recognition of necrotic neurons in the nematode C. elegans. There is a common belief that the plasma membrane of necrotic cells are ruptured, allowing the detection of phosphatidylserine (PS), a so-called “eat me” signal molecule, by specific transmembrane receptors on the surface of engulfing cells. Contrary to this belief, we found that necrotic neurons actively present PS to their outer surface through two parallel molecular mechanisms, one of which is shared by cells undergoing apoptosis, a “cell suicide” event, whereas the other is unique to necrotic cells. Ca2+-influx, a key factor that triggers necrosis, is implicated in activating a unique PS-scramblase. Our findings reveal novel necrotic cell-specific “eat me” signal-exposure mechanisms and indicate that cells that die through different mechanisms (necrosis and apoptosis) utilize both common and unique mechanisms to attract engulfing cells. They further demonstrate that C. elegans is an effective model system for studying the fate of necrotic cells.
Vyšlo v časopise:
Necrotic Cells Actively Attract Phagocytes through the Collaborative Action of Two Distinct PS-Exposure Mechanisms. PLoS Genet 11(6): e32767. doi:10.1371/journal.pgen.1005285
Kategorie:
Research Article
prolekare.web.journal.doi_sk:
https://doi.org/10.1371/journal.pgen.1005285
Souhrn
Necrosis is a type of cell death often caused by cell injury and is linked to human diseases including neuron degeneration, stroke, and cancer. Necrotic cells undergo distinct morphological changes, including swelling, before being engulfed and degraded by engulfing cells. The clearance of necrotic cells from animal bodies is important for wound healing and for preventing harmful inflammatory and autoimmune responses. However, the mechanisms by which necrotic cells are removed remain elusive. We study the recognition of necrotic neurons in the nematode C. elegans. There is a common belief that the plasma membrane of necrotic cells are ruptured, allowing the detection of phosphatidylserine (PS), a so-called “eat me” signal molecule, by specific transmembrane receptors on the surface of engulfing cells. Contrary to this belief, we found that necrotic neurons actively present PS to their outer surface through two parallel molecular mechanisms, one of which is shared by cells undergoing apoptosis, a “cell suicide” event, whereas the other is unique to necrotic cells. Ca2+-influx, a key factor that triggers necrosis, is implicated in activating a unique PS-scramblase. Our findings reveal novel necrotic cell-specific “eat me” signal-exposure mechanisms and indicate that cells that die through different mechanisms (necrosis and apoptosis) utilize both common and unique mechanisms to attract engulfing cells. They further demonstrate that C. elegans is an effective model system for studying the fate of necrotic cells.
Zdroje
1. Golstein P, Kroemer G (2007) Cell death by necrosis: towards a molecular definition. Trends Biochem Sci 32: 37–43. 17141506
2. Kroemer G, Galluzzi L, Vandenabeele P, Abrams J, Alnemri ES, Baehrecke EH, et al. (2009) Classification of cell death: recommendations of the Nomenclature Committee on Cell Death 2009. Cell Death Differ 16: 3–11. doi: 10.1038/cdd.2008.150 18846107
3. Jacobson MD, Bergeron L (2002) Cell death in the nervous system. In: Jacobson MD, McCarthy N, editors. Apoptosis, the molecular biology of programmed cell death: Oxford University Press. pp. 278–301.
4. Yamashima T (2004) Ca2+-dependent proteases in ischemic neuronal death: a conserved 'calpain-cathepsin cascade' from nematodes to primates. Cell Calcium 36: 285–293. 15261484
5. Challa S, Chan FK (2010) Going up in flames: necrotic cell injury and inflammatory diseases. Cell Mol Life Sci 67: 3241–3253. doi: 10.1007/s00018-010-0413-8 20532807
6. Whelan RS, Kaplinskiy V, Kitsis RN (2010) Cell death in the pathogenesis of heart disease: mechanisms and significance. Annu Rev Physiol 72: 19–44. doi: 10.1146/annurev.physiol.010908.163111 20148665
7. Noch E, Khalili K (2009) Molecular mechanisms of necrosis in glioblastoma: the role of glutamate excitotoxicity. Cancer Biol Ther 8: 1791–1797. 19770591
8. Vlachos M, Tavernarakis N (2010) Non-apoptotic cell death in Caenorhabditis elegans. Dev Dyn 239: 1337–1351. doi: 10.1002/dvdy.22230 20108319
9. McCall K (2010) Genetic control of necrosis—another type of programmed cell death. Curr Opin Cell Biol 22: 882–888. doi: 10.1016/j.ceb.2010.09.002 20889324
10. Zhou W, Yuan J (2014) Necroptosis in health and diseases. Semin Cell Dev Biol.
11. Moquin D, Chan FK (2010) The molecular regulation of programmed necrotic cell injury. Trends Biochem Sci 35: 434–441. doi: 10.1016/j.tibs.2010.03.001 20346680
12. Mody I, MacDonald JF (1995) NMDA receptor-dependent excitotoxicity: the role of intracellular Ca2+ release. Trends Pharmacol Sci 16: 356–359. 7491714
13. Driscoll M, Gerstbrein B (2003) Dying for a cause: invertebrate genetics takes on human neurodegeneration. Nat Rev Genet 4: 181–194. 12610523
14. Galluzzi L, Kepp O, Krautwald S, Kroemer G, Linkermann A (2014) Molecular mechanisms of regulated necrosis. Semin Cell Dev Biol 35: 24–32. doi: 10.1016/j.semcdb.2014.02.006 24582829
15. Krysko DV, D'Herde K, Vandenabeele P (2006) Clearance of apoptotic and necrotic cells and its immunological consequences. Apoptosis 11: 1709–1726. 16951923
16. Hall DH, Gu G, Garcia-Anoveros J, Gong L, Chalfie M, Driscoll M (1997) Neuropathology of degenerative cell death in Caenorhabditis elegans. J Neurosci 17: 1033–1045. 8994058
17. Poon IK, Hulett MD, Parish CR (2010) Molecular mechanisms of late apoptotic/necrotic cell clearance. Cell Death Differ 17: 381–397. doi: 10.1038/cdd.2009.195 20019744
18. Metzstein MM, Stanfield GM, Horvitz HR (1998) Genetics of programmed cell death in C. elegans: past, present and future. Trends Genet 14: 410–416. 9820030
19. Driscoll M, Chalfie M (1991) The mec-4 gene is a member of a family of Caenorhabditis elegans genes that can mutate to induce neuronal degeneration. Nature 349: 588–593. 1672038
20. Treinin M, Chalfie M (1995) A mutated acetylcholine receptor subunit causes neuronal degeneration in C. elegans. Neuron 14: 871–877. 7718248
21. Chalfie M, Sulston J (1981) Developmental genetics of the mechanosensory neurons of Caenorhabditis elegans. Dev Biol 82: 358–370. 7227647
22. Bianchi L, Gerstbrein B, Frokjaer-Jensen C, Royal DC, Mukherjee G, Royal MA, et al. (2004) The neurotoxic MEC-4(d) DEG/ENaC sodium channel conducts calcium: implications for necrosis initiation. Nat Neurosci 7: 1337–1344. 15543143
23. Ellis HM, Horvitz HR (1986) Genetic control of programmed cell death in the nematode C. elegans. Cell 44: 817–829. 3955651
24. Xu K, Tavernarakis N, Driscoll M (2001) Necrotic cell death in C. elegans requires the function of calreticulin and regulators of Ca(2+) release from the endoplasmic reticulum. Neuron 31: 957–971. 11580896
25. Chung S, Gumienny TL, Hengartner MO, Driscoll M (2000) A common set of engulfment genes mediates removal of both apoptotic and necrotic cell corpses in C. elegans. Nat Cell Biol 2: 931–937. 11146658
26. Krysko DV, Denecker G, Festjens N, Gabriels S, Parthoens E, D'Herde K, et al. (2006) Macrophages use different internalization mechanisms to clear apoptotic and necrotic cells. Cell Death Differ 13: 2011–2022. 16628234
27. Ravichandran KS (2010) Find-me and eat-me signals in apoptotic cell clearance: progress and conundrums. J Exp Med 207: 1807–1817. doi: 10.1084/jem.20101157 20805564
28. Zhou Z, Hartwieg E, Horvitz HR (2001b) CED-1 is a transmembrane receptor that mediates cell corpse engulfment in C. elegans. Cell 104: 43–56.
29. Tung TT, Nagaosa K, Fujita Y, Kita A, Mori H, Okada R, et al. (2013) Phosphatidylserine recognition and induction of apoptotic cell clearance by Drosophila engulfment receptor Draper. J Biochem 153: 483–491. doi: 10.1093/jb/mvt014 23420848
30. Miyanishi M, Tada K, Koike M, Uchiyama Y, Kitamura T, Nagata S (2007) Identification of Tim4 as a phosphatidylserine receptor. Nature 450:435–439. 17960135
31. Park D, Tosello-Trampont AC, Elliott MR, Lu M, Haney LB, Ma Z, et al. (2007) BAI1 is an engulfment receptor for apoptotic cells upstream of the ELMO/Dock180/Rac module. Nature 450:430–434. 17960134
32. Balasubramanian K, Schroit AJ (2003) Aminophospholipid asymmetry: A matter of life and death. Annu Rev Physiol 65: 701–734. 12471163
33. Vance JE, Steenbergen R (2005) Metabolism and functions of phosphatidylserine. Prog Lipid Res 44: 207–234. 15979148
34. Segawa K, Kurata S, Yanagihashi Y, Brummelkamp TR, Matsuda F, Nagata S (2014) Caspase-mediated cleavage of phospholipid flippase for apoptotic phosphatidylserine exposure. Science 344: 1164–1168. doi: 10.1126/science.1252809 24904167
35. Sims PJ, Wiedmer T (2001) Unraveling the mysteries of phospholipid scrambling. Thromb Haemost 86: 266–275. 11487015
36. Suzuki J, Umeda M, Sims PJ, Nagata S (2010) Calcium-dependent phospholipid scrambling by TMEM16F. Nature 468: 834–838. doi: 10.1038/nature09583 21107324
37. Suzuki J, Fujii T, Imao T, Ishihara K, Kuba H, Nagata S (2013) Calcium-dependent phospholipid scramblase activity of TMEM16 protein family members. J Biol Chem 288: 13305–13316. doi: 10.1074/jbc.M113.457937 23532839
38. Suzuki J, Denning DP, Imanishi E, Horvitz HR, Nagata S (2013) Xk-related protein 8 and CED-8 promote phosphatidylserine exposure in apoptotic cells. Science 341: 403–406. doi: 10.1126/science.1236758 23845944
39. Chen YZ, Mapes J, Lee ES, Skeen-Gaar RR, Xue D (2013) Caspase-mediated activation of Caenorhabditis elegans CED-8 promotes apoptosis and phosphatidylserine externalization. Nat Commun 4: 2726. doi: 10.1038/ncomms3726 24225442
40. Hamon Y, Broccardo C, Chambenoit O, Luciani MF, Toti F, Chaslin S, et al. (2000) ABC1 promotes engulfment of apoptotic cells and transbilayer redistribution of phosphatidylserine. Nat Cell Biol 2: 399–406. 10878804
41. Alder-Baerens N, Muller P, Pohl A, Korte T, Hamon Y, Chimini G, et al. (2005) Headgroup-specific exposure of phospholipids in ABCA1-expressing cells. J Biol Chem 280: 26321–26329. 15905177
42. Williamson P, Halleck MS, Malowitz J, Ng S, Fan X, Krahling S, et al. (2007) Transbilayer phospholipid movements in ABCA1-deficient cells. PLoS One 2: e729. 17710129
43. Venegas V, Zhou Z (2007) Two alternative mechanisms that regulate the presentation of apoptotic cell engulfment signal in Caenorhabditis elegans. Mol Biol Cell 18: 3180–3192. 17567952
44. Zong WX, Thompson CB (2006) Necrotic death as a cell fate. Genes Dev 20: 1–15. 16391229
45. Hedgecock EM, Sulston JE, Thomson JN (1983) Mutations affecting programmed cell deaths in the nematode Caenorhabditis elegans. Science 220: 1277–1279. 6857247
46. Sulston JE, Horvitz HR (1977) Post-embryonic cell lineages of the nematode, Caenorhabditis elegans. Dev Biol 56: 110–156. 838129
47. Sulston JE, Schierenberg E, White JG, Thomson JN (1983) The embryonic cell lineage of the nematode Caenorhabditis elegans. Dev Biol 100: 64–119. 6684600
48. Li Z, Lu N, He X, Zhou Z (2013) Monitoring the clearance of apoptotic and necrotic cells in the nematode Caenorhabditis elegans. Methods Mol Biol 1004: 183–202. doi: 10.1007/978-1-62703-383-1_14 23733578
49. Hamelin M, Scott IM, Way JC, Culotti JG (1992) The mec-7 beta-tubulin gene of Caenorhabditis elegans is expressed primarily in the touch receptor neurons. EMBO J 11: 2885–2893. 1639062
50. Grant B, Greenwald I (1997) Structure, function, and expression of SEL-1, a negative regulator of LIN-12 and GLP-1 in C. elegans. Development 124: 637–644. 9043078
51. Okkema PG, Harrison SW, Plunger V, Aryana A, Fire A (1993) Sequence requirements for myosin gene expression and regulation in Caenorhabditis elegans. Genetics 135: 385–404. 8244003
52. Hong K, Driscoll M (1994) A transmembrane domain of the putative channel subunit MEC-4 influences mechanotransduction and neurodegeneration in C. elegans. Nature 367: 470–473. 8107806
53. Treinin M, Gillo B, Liebman L, Chalfie M (1998) Two functionally dependent acetylcholine subunits are encoded in a single Caenorhabditis elegans operon. Proc Natl Acad Sci U S A 95: 15492–15495. 9860996
54. Wu Y, Horvitz HR (1998a) The C. elegans cell corpse engulfment gene ced-7 encodes a protein similar to ABC transporters. Cell 93: 951–960. 9635425
55. Shen Q, He B, Lu N, Conradt B, Grant BD, Zhou Z (2013) Phagocytic receptor signaling regulates clathrin and epsin-mediated cytoskeletal remodeling during apoptotic cell engulfment in C. elegans. Development 140: 3230–3243. doi: 10.1242/dev.093732 23861060
56. Choi J, Richards KL, Cinar HN, Newman AP (2006) N-ethylmaleimide sensitive factor is required for fusion of the C. elegans uterine anchor cell. Dev Biol 297: 87–102. 16769048
57. Wang Y, Alam T, Hill-Harfe K, Lopez AJ, Leung CK, Iribarne D, et al. (2013) Phylogenetic, expression, and functional analyses of anoctamin homologs in Caenorhabditis elegans. Am J Physiol Regul Integr Comp Physiol 305: R1376–1389. doi: 10.1152/ajpregu.00303.2012 24049119
58. Stanfield GM, Horvitz HR (2000) The ced-8 gene controls the timing of programmed cell deaths in C. elegans. Mol Cell 5: 423–433. 10882128
59. Denecker G, Vercammen D, Steemans M, Vanden Berghe T, Brouckaert G, Van Loo G, et al. (2001) Death receptor-induced apoptotic and necrotic cell death: differential role of caspases and mitochondria. Cell Death Differ 8: 829–840. 11526436
60. Krysko DV, Brouckaert G, Kalai M, Vandenabeele P, D'Herde K (2003) Mechanisms of internalization of apoptotic and necrotic L929 cells by a macrophage cell line studied by electron microscopy. J Morphol 258: 336–345. 14584035
61. Elliott MR, Ravichandran KS (2010) Clearance of apoptotic cells: implications in health and disease. J Cell Biol 189: 1059–1070. doi: 10.1083/jcb.201004096 20584912
62. Hajos F, Garthwaite G, Garthwaite J (1986) Reversible and irreversible neuronal damage caused by excitatory amino acid analogues in rat cerebellar slices. Neuroscience 18: 417–436. 3526173
63. van den Eijnde SM, Boshart L, Baehrecke EH, De Zeeuw CI, Reutelingsperger CPM, Vermeij-Keers C (1998) Cell surface exposure of phosphatidylserine during apoptosis is phylogenetically conserved. Apoptosis 3: 9–16. 14646513
64. Wang X, Wang J, Gengyo-Ando K, Gu L, Sun CL, Yang C, et al. (2007) C. elegans mitochondrial factor WAH-1 promotes phosphatidylserine externalization in apoptotic cells through phospholipid scramblase SCRM-1. Nat Cell Biol 9: 541–549. 17401362
65. Zullig S, Neukomm LJ, Jovanovic M, Charette SJ, Lyssenko NN, Halleck MS, et al. (2007) Aminophospholipid translocase TAT-1 promotes phosphatidylserine exposure during C. elegans apoptosis. Curr Biol 17: 994–999. 17540571
66. Hanayama R, Tanaka M, Miwa K, Shinohara A, Iwamatsu A, Nagata S (2002) Identification of a factor that links apoptotic cells to phagocytes. Nature 417: 182–187. 12000961
67. Wang X, Li W, Zhao D, Liu B, Shi Y, Chen B, et al. (2010) Caenorhabditis elegans transthyretin-like protein TTR-52 mediates recognition of apoptotic cells by the CED-1 phagocyte receptor. Nat Cell Biol 12: 655–664. doi: 10.1038/ncb2068 20526330
68. Schlegel RA, Williamson P (2007) P.S. to PS (phosphatidylserine)—pertinent proteins in apoptotic cell clearance. Sci STKE 2007: pe57. 17940275
69. Chen B, Liu Q, Ge Q, Xie J, Wang ZW (2007) UNC-1 regulates gap junctions important to locomotion in C. elegans. Curr Biol 17: 1334–1339. 17658257
70. Hong X, Zang J, White J, Wang C, Pan CH, Zhao R, et al. (2010) Interaction of JMJD6 with single-stranded RNA. Proc Natl Acad Sci U S A 107: 14568–14572. doi: 10.1073/pnas.1008832107 20679243
71. Webby CJ, Wolf A, Gromak N, Dreger M, Kramer H, Kessler B, et al. (2009) Jmjd6 catalyses lysyl-hydroxylation of U2AF65, a protein associated with RNA splicing. Science 325: 90–93. doi: 10.1126/science.1175865 19574390
72. Yang H, Chen YZ, Zhang Y, Wang X, Zhao X, Godfroy JI 3rd, et al. (2015) A lysine-rich motif in the phosphatidylserine receptor PSR-1 mediates recognition and removal of apoptotic cells. Nat Commun 6: 5717. doi: 10.1038/ncomms6717 25564762
73. Wang X, Wu YC, Fadok VA, Lee MC, Gengyo-Ando K, Cheng LC, et al. (2003) Cell corpse engulfment mediated by C. elegans phosphatidylserine receptor through CED-5 and CED-12. Science 302: 1563–1566. 14645848
74. Rigot V, Hamon Y, Chambenoit O, Alibert M, Duverger N, Chimini G (2002) Distinct sites on ABCA1 control distinct steps required for cellular release of phospholipids. J Lipid Res 43: 2077–2086. 12454269
75. Mapes J, Chen YZ, Kim A, Mitani S, Kang BH, Xue D (2012) CED-1, CED-7, and TTR-52 regulate surface phosphatidylserine expression on apoptotic and phagocytic cells. Curr Biol 22: 1267–1275. doi: 10.1016/j.cub.2012.05.052 22727702
76. Pedemonte N, Galietta LJ (2014) Structure and function of TMEM16 proteins (anoctamins). Physiol Rev 94: 419–459. doi: 10.1152/physrev.00039.2011 24692353
77. Yang H, Kim A, David T, Palmer D, Jin T, Tien J, et al. (2012) TMEM16F forms a Ca2+-activated cation channel required for lipid scrambling in platelets during blood coagulation. Cell 151: 111–122. doi: 10.1016/j.cell.2012.07.036 23021219
78. Wojda U, Salinska E, Kuznicki J (2008) Calcium ions in neuronal degeneration. IUBMB Life 60: 575–590. doi: 10.1002/iub.91 18478527
79. Sattler R, Tymianski M (2001) Molecular mechanisms of glutamate receptor-mediated excitotoxic neuronal cell death. Mol Neurobiol 24: 107–129. 11831548
80. Mattson MP, LaFerla FM, Chan SL, Leissring MA, Shepel PN, Geiger JD (2000) Calcium signaling in the ER: its role in neuronal plasticity and neurodegenerative disorders. Trends Neurosci 23: 222–229. 10782128
81. Mano I, Driscoll M (2009) Caenorhabditis elegans glutamate transporter deletion induces AMPA-receptor/adenylyl cyclase 9-dependent excitotoxicity. J Neurochem 108: 1373–1384. doi: 10.1111/j.1471-4159.2008.05804.x 19054279
82. Mattson MP (2007) Calcium and neurodegeneration. Aging Cell 6: 337–350. 17328689
83. Brenner S (1974) The genetics of Caenorhabditis elegans. Genetics 77: 71–94. 4366476
84. Riddle DL, Blumenthal T, Meyer BJ, Priess JR, editors (1997) C. elegans II. Plainview, NY: Cold Spring harbor Laboratory Press.
85. Frokjaer-Jensen C, Davis MW, Hopkins CE, Newman BJ, Thummel JM, Olesen SP, et al. (2008) Single-copy insertion of transgenes in Caenorhabditis elegans. Nat Genet 40: 1375–1383. doi: 10.1038/ng.248 18953339
86. Jin Y (1999) Transformation. In: Hope IA, editor. C elegans, a practical approach. Oxford: Oxford University Press. pp. 69–96.
87. Bloom L, Horvitz HR (1997) The Caenorhabditis elegans gene unc-76 and its human homologs define a new gene family involved in axonal outgrowth and fasciculation. Proc Natl Acad Sci U S A 94: 3414–3419. 9096408
88. Campbell RE, Tour O, Palmer AE, Steinbach PA, Baird GS, Zacharias DA, et al. (2002) A monomeric red fluorescent protein. Proc Natl Acad Sci U S A 99: 7877–7882. 12060735
89. Shaner NC, Campbell RE, Steinbach PA, Giepmans BN, Palmer AE, Tsien RY (2004) Improved monomeric red, orange and yellow fluorescent proteins derived from Discosoma sp. red fluorescent protein. Nat Biotechnol 22: 1567–1572. 15558047
90. Fares H, Greenwald I (2001) Genetic analysis of endocytosis in Caenorhabditis elegans: coelomocyte uptake defective mutants. Genetics 159: 133–145. 11560892
91. Yu X, Odera S, Chuang CH, Lu N, Zhou Z (2006) C. elegans Dynamin mediates the signaling of phagocytic receptor CED-1 for the engulfment and degradation of apoptotic cells. Dev Cell 10: 743–757. 16740477
92. Kuraishi T, Nakagawa Y, Nagaosa K, Hashimoto Y, Ishimoto T, Moki T, et al. (2009) Pretaporter, a Drosophila protein serving as a ligand for Draper in the phagocytosis of apoptotic cells. EMBO J 28: 3868–3878. doi: 10.1038/emboj.2009.343 19927123
93. Kawasaki Y, Nakagawa A, Nagaosa K, Shiratsuchi A, Nakanishi Y (2002) Phosphatidylserine binding of class B scavenger receptor type I, a phagocytosis receptor of testicular sertoli cells. J Biol Chem 277: 27559–27566. 12016218
94. Shiratsuchi A, Umeda M, Ohba Y, Nakanishi Y (1997) Recognition of phosphatidylserine on the surface of apoptotic spermatogenic cells and subsequent phagocytosis by Sertoli cells of the rat. J Biol Chem 272: 2354–2358. 8999945
95. Jain PT, Chang SH, Gutry PP, Berezesky IK, Trump BF (1993) The relationship between [Ca2+]i and cell death using an in vivo model: a study using the ced-1 mutant strain of C. elegans. Toxicol Pathol 21: 572–583. 8052804
Štítky
Genetika Reprodukčná medicínaČlánok vyšiel v časopise
PLOS Genetics
2015 Číslo 6
- Je „freeze-all“ pro všechny? Odborníci na fertilitu diskutovali na virtuálním summitu
- Gynekologové a odborníci na reprodukční medicínu se sejdou na prvním virtuálním summitu
Najčítanejšie v tomto čísle
- Non-reciprocal Interspecies Hybridization Barriers in the Capsella Genus Are Established in the Endosperm
- Translational Upregulation of an Individual p21 Transcript Variant by GCN2 Regulates Cell Proliferation and Survival under Nutrient Stress
- Exome Sequencing of Phenotypic Extremes Identifies and as Interacting Modifiers of Chronic Infection in Cystic Fibrosis
- The Human Blood Metabolome-Transcriptome Interface