Granulocyte heterochromatin: defining the epigenome

<p>Abstract</p> <p>Background</p> <p>Mammalian blood neutrophilic granulocytes are terminally differentiated cells, possessing extensive heterochromatin and lobulated (or ring-shaped) nuclei. Despite the extensive amount of heterochromatin, neutrophils are capable of in...

Full description

Bibliographic Details
Main Authors: Olins Ada L, Olins Donald E
Format: Article
Language:English
Published: BMC 2005-11-01
Series:BMC Cell Biology
Online Access:http://www.biomedcentral.com/1471-2121/6/39
_version_ 1818064209392435200
author Olins Ada L
Olins Donald E
author_facet Olins Ada L
Olins Donald E
author_sort Olins Ada L
collection DOAJ
description <p>Abstract</p> <p>Background</p> <p>Mammalian blood neutrophilic granulocytes are terminally differentiated cells, possessing extensive heterochromatin and lobulated (or ring-shaped) nuclei. Despite the extensive amount of heterochromatin, neutrophils are capable of increased gene expression, when activated by bacterial infection. Understanding the mechanisms of transcriptional repression and activation in neutrophils requires detailing the chromatin epigenetic markers, which are virtually undescribed in this cell type. Much is known about the heterochromatin epigenetic markers in other cell-types, permitting a basis for comparison with those of mature normal neutrophilic granulocytes.</p> <p>Results</p> <p>Immunostaining and immunoblotting procedures were employed to study the presence of repressive histone modifications and HP1 proteins in normal human and mouse blood neutrophils, and in vitro differentiated granulocytes of the mouse promyelocytic (MPRO) system. A variety of repressive histone methylation markers were detectable in these granulocytes (di- and trimethylated H3K9; mono-, di- and trimethyl H3K27; di- and trimethyl H4K20). However, a paucity of HP1 proteins was noted. These granulocytes revealed negligible amounts of HP1 α and β, but exhibited detectable levels of HP1 γ. Of particular interest, mouse blood and MPRO undifferentiated cells and granulocytes revealed clear co-localization of trimethylated H3K9, trimethylated H4K20 and HP1 γ with pericentric heterochromatin.</p> <p>Conclusion</p> <p>Mature blood neutrophils possess some epigenetic heterochromatin features that resemble those of well-studied cells, such as lymphocytes. However, the apparent paucity of HP1 proteins in neutrophils suggests that heterochromatin organization and binding to the nuclear envelope may differ in this cell-type. Future investigations should follow changes in epigenetic markers and levels of HP1 proteins during granulopoiesis and bacterial activation of neutrophils.</p>
first_indexed 2024-12-10T14:32:22Z
format Article
id doaj.art-d495fd3bf8ef4fffae8933f71f98b406
institution Directory Open Access Journal
issn 1471-2121
language English
last_indexed 2024-12-10T14:32:22Z
publishDate 2005-11-01
publisher BMC
record_format Article
series BMC Cell Biology
spelling doaj.art-d495fd3bf8ef4fffae8933f71f98b4062022-12-22T01:44:55ZengBMCBMC Cell Biology1471-21212005-11-01613910.1186/1471-2121-6-39Granulocyte heterochromatin: defining the epigenomeOlins Ada LOlins Donald E<p>Abstract</p> <p>Background</p> <p>Mammalian blood neutrophilic granulocytes are terminally differentiated cells, possessing extensive heterochromatin and lobulated (or ring-shaped) nuclei. Despite the extensive amount of heterochromatin, neutrophils are capable of increased gene expression, when activated by bacterial infection. Understanding the mechanisms of transcriptional repression and activation in neutrophils requires detailing the chromatin epigenetic markers, which are virtually undescribed in this cell type. Much is known about the heterochromatin epigenetic markers in other cell-types, permitting a basis for comparison with those of mature normal neutrophilic granulocytes.</p> <p>Results</p> <p>Immunostaining and immunoblotting procedures were employed to study the presence of repressive histone modifications and HP1 proteins in normal human and mouse blood neutrophils, and in vitro differentiated granulocytes of the mouse promyelocytic (MPRO) system. A variety of repressive histone methylation markers were detectable in these granulocytes (di- and trimethylated H3K9; mono-, di- and trimethyl H3K27; di- and trimethyl H4K20). However, a paucity of HP1 proteins was noted. These granulocytes revealed negligible amounts of HP1 α and β, but exhibited detectable levels of HP1 γ. Of particular interest, mouse blood and MPRO undifferentiated cells and granulocytes revealed clear co-localization of trimethylated H3K9, trimethylated H4K20 and HP1 γ with pericentric heterochromatin.</p> <p>Conclusion</p> <p>Mature blood neutrophils possess some epigenetic heterochromatin features that resemble those of well-studied cells, such as lymphocytes. However, the apparent paucity of HP1 proteins in neutrophils suggests that heterochromatin organization and binding to the nuclear envelope may differ in this cell-type. Future investigations should follow changes in epigenetic markers and levels of HP1 proteins during granulopoiesis and bacterial activation of neutrophils.</p>http://www.biomedcentral.com/1471-2121/6/39
spellingShingle Olins Ada L
Olins Donald E
Granulocyte heterochromatin: defining the epigenome
BMC Cell Biology
title Granulocyte heterochromatin: defining the epigenome
title_full Granulocyte heterochromatin: defining the epigenome
title_fullStr Granulocyte heterochromatin: defining the epigenome
title_full_unstemmed Granulocyte heterochromatin: defining the epigenome
title_short Granulocyte heterochromatin: defining the epigenome
title_sort granulocyte heterochromatin defining the epigenome
url http://www.biomedcentral.com/1471-2121/6/39
work_keys_str_mv AT olinsadal granulocyteheterochromatindefiningtheepigenome
AT olinsdonalde granulocyteheterochromatindefiningtheepigenome