Lamins of ocular lens epithelial cells.
Experiments were performed to characterize a prominent nuclear matrix (NM) protein isolated from tissue cultured mouse lens epithelial cells. This NM protein was separated by SDS-PAGE and the stained gel band was analyzed by mass spectroscopy. Blast analysis of the amino acid sequence derived by mass spectroscopy revealed the presence of Lamin C in the NM of the mouse lens epithelial cells. We also examined nuclear proteins of adult and fetal human lenses. Data collected from these experiments showed the presence of Lamin C in both adult and fetal lens cells. However fetal lens cells only show Lamin C dimers, whereas adult human lens contained dimers, monomers and degraded Lamin C. Early and late passaged tissue cultured mouse lens epithelial cells also contained Lamin C in the nucleus with a preponderance of the dimer in the early passaged cells. The biological significance of the presence of dimers in human fetal lens cells and early passaged mouse lens cells is not known. However, it could suggest an enhanced docking capability of Lamin C dimers for other physiologically important nuclear proteins.
Bagchi
M
M
Department of Anatomy and Cell Biology, Wayne State University, School of Medicine, Detroit, MI 48201, USA. mbagchi@med.wayne.edu
Petrov
T
T
Maisel
H
H
D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D004847:Epithelial Cells / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D006801:Humans; D015151:Immunoblotting; D034904:Lamin Type A / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D034882:Lamins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D007908:Lens, Crystalline / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D015530:Nuclear Matrix / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D020539:Sequence Analysis, Protein; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013997:Time Factors
D034904:Lamin Type A; D034882:Lamins; D009687:Nuclear Proteins; C440308:lamin C