The human granulocyte nucleus: Unusual nuclear envelope and heterochromatin composition

Eur J Cell Biol. 2008 May;87(5):279-90. doi: 10.1016/j.ejcb.2008.02.007. Epub 2008 Apr 8.

Abstract

The human blood granulocyte (neutrophil) is adapted to find and destroy infectious agents. The nucleus of the human neutrophil has a segmented appearance, consisting of a linear or branched array of three or four lobes. Adequate levels of lamin B receptor (LBR) are necessary for differentiation of the lobulated nucleus. The levels of other components of the nuclear envelope may also be important for nuclear shape determination. In the present study, immunostaining and immunoblotting procedures explored the levels of various components of the nuclear envelope and heterochromatin, comparing freshly isolated human neutrophils with granulocytic forms of HL-60 cells, a tissue culture model system. In comparison to granulocytic HL-60 cells, blood neutrophil nuclear envelopes contain low-to-negligible amounts of LBR, lamins A/C, B1 and B2, LAP2beta and emerin. Surprisingly, a "mitotic" chromosome marker, H3(S10)phos, is elevated in neutrophil nuclei, compared to granulocytic HL-60 cells. Furthermore, neutrophil nuclei appear to be more fragile to methanol fixation, than observed with granulocytic HL-60 cells. Thus, the human neutrophil nucleus appears to be highly specialized, possessing a paucity of nuclear envelope-stabilizing proteins. In consequence, the neutrophil nucleus appears to be very malleable, supporting rapid migration through tight tissue spaces.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Nucleus / metabolism
  • Cell Nucleus Shape
  • Chromosomal Proteins, Non-Histone / metabolism
  • DNA-Binding Proteins / metabolism
  • Female
  • Granulocytes / cytology*
  • Granulocytes / metabolism
  • HL-60 Cells
  • Heterochromatin / metabolism*
  • Histones / metabolism
  • Humans
  • Immunoblotting
  • Lamin Type B / metabolism
  • Lamins / metabolism
  • Male
  • Membrane Proteins / metabolism
  • Methanol
  • Mitosis
  • Neutrophils / cytology
  • Neutrophils / metabolism
  • Nuclear Envelope / metabolism*
  • Nuclear Proteins / metabolism
  • Receptors, Cytoplasmic and Nuclear / metabolism
  • Tissue Fixation

Substances

  • Chromosomal Proteins, Non-Histone
  • DNA-Binding Proteins
  • Heterochromatin
  • Histones
  • Lamin Type B
  • Lamins
  • Membrane Proteins
  • Nuclear Proteins
  • Receptors, Cytoplasmic and Nuclear
  • emerin
  • lamin B receptor
  • lamin B1
  • lamina-associated polypeptide 2
  • heterochromatin-specific nonhistone chromosomal protein HP-1
  • Methanol