Presence of a novel nuclear lamina protein in Raji cells.
In mammalian tissues, the nuclear lamina is composed of the major lamins A, B, and C, and minor lamins D/E. Although lamin B is present in all cell types, lamins A and C are absent from embryonic cells and most undifferentiated cells from hematopoietic lineage. We have investigated the nuclear lamina protein composition of the Raji cell line, lymphoblast-like cells established from a Burkitt lymphoma patient. Lamins A and C were confirmed absent by immunodetection and Northern blot analysis. Besides lamins B and D/E, a protein migrating around 71 kilodaltons was recognized by a serum directed against the nuclear lamina of BHK-21 fibroblasts. Cellular localization by sequential extraction established this 71-kilodalton protein as an exclusive component of the nuclear lamina fraction. These results indicate that the nuclear lamina has a more complex composition than previously thought to be the case for cells devoid of lamins A and C.
Foisy
S
S
Institut du Cancer de Montréal, Que., Canada.
Joly
E
E
Sakr
F
F
Levac
P
P
Bibor-Hardy
V
V
D000818:Animals; D015152:Blotting, Northern; D002051:Burkitt Lymphoma / Q000737:chemistry*; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D006367:HeLa Cells; D006801:Humans; D007124:Immunoenzyme Techniques; D034921:Lamin Type B; D034882:Lamins; D009687:Nuclear Proteins / Q000032:analysis*; D010449:Peptide Mapping; D014407:Tumor Cells, Cultured
D034921:Lamin Type B; D034882:Lamins; D009687:Nuclear Proteins