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Mammalian alpha I-spectrin is a neofunctionalized polypeptide adapted to small highly deformable erythrocytes.

By Marcela Salomao, Xiuli An, Walter B. Gratzer, Narla Mohandas and Anthony J. Baines

Abstract

Mammalian red blood cells, unlike those of other vertebrates, must withstand the rigors of circulation in the absence of new protein synthesis. Key to this is plasma membrane elasticity deriving from the protein spectrin, which forms a network on the cytoplasmic face. Spectrin is a tetramer (alphabeta)(2), made up of alphabeta dimers linked head to head. We show here that one component of erythrocyte spectrin, alphaI, is encoded by a gene unique to mammals. Phylogenetic analysis suggests that the other alpha-spectrin gene (alphaII) common to all vertebrates was duplicated after the emergence of amphibia, and that the resulting alphaI gene was preserved only in mammals. The activities of alphaI and alphaII spectrins differ in the context of the human red cell membrane. An alphaI-spectrin fragment containing the site of head-to-head interaction with the beta-chain binds more weakly than the corresponding alphaII fragment to this site. The latter competes so strongly with endogenous alphaI as to cause destabilization of membranes at 100-fold lower concentration than the alphaI fragment. The efficacies of alphaI/alphaII chimeras indicate that the partial structural repeat, which binds to the complementary beta-spectrin element, and the adjacent complete repeat together determine the strength of the dimer-dimer interaction on the membrane. Alignment of all available alpha-spectrin N-terminal sequences reveals three blocks of sequence unique to alphaI. Furthermore, human alphaII-spectrin is closer to fruitfly alpha-spectrin than to human alphaI-spectrin, consistent with adaptation of alphaI to new functions. We conclude that alphaI-spectrin represents a neofunctionalized spectrin adapted to the rapid make and break of tetramers

Topics: Q1
Year: 2006
OAI identifier: oai:kar.kent.ac.uk:14

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Citations

  1. (1992). [1973]) and Girard
  2. (1990). 125) quoted in Arthur,
  3. (1992). 20) quoted in Arthur,
  4. (2007). 221. Dingley and Mollica, The Human Body as a Terrorist Weapon - doi
  5. (1992). 24) quoted in Arthur,
  6. (2007). 29/11/03, p.1 and 12-13. Dingley and Mollica, The Human Body as a Terrorist Weapon -
  7. (1992). 75) quoted in Arthur,
  8. (1999). A Community in crisis”. Dungiven: and the 1981 Republican Hunger Strikes,
  9. (1981). A History of doi
  10. (1981). A History of Northern Ireland, doi
  11. (1993). A History of Warfare, doi
  12. (1992). A Noble Death. Suicide and Martyrdom among Christians and Jews in Antiquity, Harper San Francisco (Calif.), doi
  13. (1998). A Reply to White's Non-Sectarian Thesis of PIRA Targeting', Terrorism and Political Violence, doi
  14. (1994). Ancestral Voices,
  15. (1999). Bandit Country, London: Coronet,
  16. (1997). Between War and Peace,
  17. Bic McFarlane quoted in Campbell et al.,
  18. Bik McFarlane quoted in Campbell et al.,
  19. (1996). chapter 18. This was also the core of many early sociologists, such as Durkheim, Tonnies, Weber or Marx, whose work as is recalled in R Nisbett, The Sociological Tradition,
  20. chapter 8. James Dingley, jc.dingley@cybernos-ac.co.uk Marcello Mollica,
  21. Chechnya rebels in Russian prisons; members of Turkish leftist organizations and Kurdish
  22. (1982). Culture and Anarchy in
  23. (1982). Culture and Anarchy in Ireland,
  24. (2000). Demography, State and Society, doi
  25. (1993). E kedourie,
  26. (1997). Fighting for doi
  27. (1997). Fighting for Ireland,
  28. Fr Faul quoted in O’Malley,
  29. From a letter smuggled inside Maze/Long Kesh prison, Laurence McKeown quoted in Campbell et al.,
  30. (1981). From the so-called doi
  31. From the so-called “Prisoners’ Statement at
  32. From the so-called “Prisoners’ Statement at Start of the First Hunger Strike”.
  33. (2000). Fundamentalism, doi
  34. (1989). God Save Ulster, doi
  35. (1998). Grimmege Zeiten: The Influence of Herder, Lessing and the Grimm Brothers on the Nationalism of Young Irelanders',
  36. (1997). ibidem, chapter 5. The Independent,
  37. (1991). Imagined Communities, doi
  38. (2001). Imprisonment in England and Wales. A Concise History, doi
  39. (1986). Intimidation and the Control of Conflict in doi
  40. (1973). Ireland Since the Famine,
  41. Jaz McCann quoted in Campbell et al.,
  42. (1999). Lost Lives. The Stories of the men, women and children who died as a result of the Northern Ireland Troubles, Mainstream Publishing, Edinburgh and London, doi
  43. Marching Down the Garvaghy Road' doi
  44. (1997). Material Conflicts, doi
  45. McKeown quoted in Campbell et al.,
  46. (1996). Nationalism and the Idiocy of the Countryside; The Case of Serbia', doi
  47. (1995). Nationalism in doi
  48. (1994). On the 1980-1981 Hunger Strike in Northern Ireland see Beresford, ibidem; Brian Campbell, Laurence McKeown, Felim O’Hagan (eds.), Nor Meekly Serve My Time. The H-Block Struggle 1976-1981, Beyond The Pale Publications,
  49. (1994). On the INLA history see Jack Holland and Henry McDonald, INLA. Deadly Divisions. The Story of One of Ireland’s Most Ruthless Organisations, Torc,
  50. (1997). Political Crime, Needham Heights: Allyn and Bacon,
  51. (1984). Political Realities. Government & Politics of Northern Ireland,
  52. (1989). Political Terrorism, doi
  53. (1997). Politics of Antagonism, doi
  54. Popular Front for Liberation of Palestine members in Israel; Iraqi and Afghani guerrilla; Chechnya rebels in Russia; Al-Quaeda and related organizations all around the world.
  55. (2002). Propaganda 1: Advanced Nationalist Propaganda and Moralistic Revolution', doi
  56. (1964). quoted in Michael Humphrey, The Politics of Atrocity and Reconciliation. From Terror to Trauma,
  57. (1997). Reading” Violence: Ireland
  58. (1991). Religion and Social Theory,
  59. (2000). Roots of Romanticism, doi
  60. Sacrifice, Gift and the Social Logic of Muslim Suicide Bombers', doi
  61. (1991). Science and Religion: Some Historical Perspectives, doi
  62. (1997). Science and Society in Ireland, Belfast: Institute of Irish Studies,
  63. Seanna Walsh quoted in Campbell et al., ibidem,
  64. (1970). Sociology of Death. An Analysis of Death-Related Behaviour, doi
  65. (2001). Sociology, doi
  66. Symbolism and Sacrifice in Terrorism' doi
  67. (1987). Ten Men Dead.
  68. (2001). Terror in the Mind of God, doi
  69. (1996). Terrorism and Taboo,
  70. (1989). The Ability to Mourn. Disillusionment and the Social Origins of Psychoanalysis, doi
  71. (2003). The Assassins, doi
  72. (1984). The Basque Insurgents, Wisconsin:
  73. (1993). The Clash of Civilizations', Foreign affairs, summer, doi
  74. (1997). The Construction of Nationhood, doi
  75. (2000). The Crowned Harp, doi
  76. (1984). The Division of Labour in Society, doi
  77. (2000). The Irish protestant Churches in the Twentieth Century, doi
  78. (1904). The King’s Threshold, doi
  79. (1977). The Logic of International Relations,
  80. (1982). The moral justification of suicide,
  81. (2000). The Northern Ireland Peace Process, doi
  82. (1991). The Politics of Nationalism and Ethnicity', doi
  83. (1976). The Protestant Ethic and the Spirit of Capitalism, London: Allen and Unwin, doi
  84. (2003). The Scottish Enlightenment, London: Fourth Estate,
  85. (2003). The Search for the Terrorist Personality', doi
  86. (2003). The Social and Psychological Characteristics of terrorism and Terrorists, conference paper NUPI, doi
  87. (1979). The Social Origins of the Irish Land War, doi
  88. (1999). The Sociological Tradition, doi
  89. The Terrorist - Developing a Profile',
  90. The Terrorists in Their Own Words', doi
  91. (1964). The Theory of Social and Economic Organisation',
  92. (1998). The Trouble With Guns Belfast: Blackstaff,
  93. (1998). The Two Irelands, doi
  94. (1991). Troubled Times. Forthnight Magazine and the Troubles in Northern Ireland 1970-1991, with a Chronology of Events,

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