Intranuclear distribution of HMGI/Y proteins. An immunocytochemical study.
The intranuclear distribution of HMGI/Y proteins was analyzed by immunofluorescent staining in several cell lines using a polyclonal antibody that stained a fibrogranular network. In actively growing 3T3 fibroblasts, HMGI/Y proteins were mainly localized to heterochromatin masses, whereas in quiescent cells they were more diffusely distributed. Double labeling experiments showed a co-localization of HMGI/Y with DNA topoisomerase IIalpha. These results are in agreement with previously published biochemical data and indicate a possible involvement of HMGI/Y proteins in several nuclear functions, including chromatin organization and gene expression.
Martelli
A M
AM
Dipartimento di Morfologia Umana, Università di Trieste, Trieste, Italy.
Riccio
M
M
Bareggi
R
R
Manfioletti
G
G
Tabellini
G
G
Baldini
G
G
Narducci
P
P
Giancotti
V
V
D016475:3T3 Cells; D000818:Animals; D002453:Cell Cycle; D002460:Cell Line; D002467:Cell Nucleus / Q000737:chemistry*; D004264:DNA Topoisomerases, Type I / Q000032:analysis; D025741:HMGA1a Protein; D006367:HeLa Cells / Q000378:metabolism; D006570:Heterochromatin / Q000737:chemistry; D006609:High Mobility Group Proteins / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D051381:Rats; D013961:Thyroid Gland / Q000737:chemistry; D014157:Transcription Factors / Q000032:analysis*
D006570:Heterochromatin; D006609:High Mobility Group Proteins; D014157:Transcription Factors; D025741:HMGA1a Protein; D004264:DNA Topoisomerases, Type I