Limited expression of nuclear pore membrane glycoprotein 210 in cell lines and tissues suggests cell-type specific nuclear pores in metazoans.
The nuclear pore complex (NPC) is the only known gateway for nucleocytoplasmic traffic. The nuclear pore membrane glycoprotein 210 (POM210/gp210) is considered to be important for the assembly and structure of pore complexes in metazoan cells. However, here we demonstrate cell-type specific expression of the gp210 protein during mouse organogenesis. As shown previously for its mRNA, distinct expression of the gp210 was seen in developing epithelia and some other cell types, whereas it was undetectable in nuclei of several other embryonic tissue compartments. In sharp contrast, monoclonal antibody 414 recognizing four non-membrane nucleoporins, stained the nuclear envelope of all cell types. In four cultured mouse cell lines, gp210 mRNA and protein were below detection levels, in contrast to some other nucleoporins tested. Distinct expression of gp210 mRNA and protein was seen in cultured mouse embryonic stem (ES) cells. These findings support the view of cell-type specific NPCs in metazoans and that the gp210 gene is regulated by cell-type specific control elements not shared by other nucleoporins. Although it cannot be excluded that very low expression levels of gp210 are sufficient to allow attachment of NPCs, a more likely alternative is that it has cell-type specific functions.
Olsson
Magnus
M
Department of Cell and Molecular Biology, BMC B12, Lund University, SE-221 84, Lund, Sweden.
Schéele
Susanne
S
Ekblom
Peter
P
D016475:3T3 Cells; D021581:Active Transport, Cell Nucleus / Q000502:physiology*; D000818:Animals; D002451:Cell Compartmentation / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology*; D016764:Cell Polarity / Q000502:physiology; D004847:Epithelial Cells / Q000378:metabolism* / Q000648:ultrastructure; D005333:Fetus; D005455:Fluorescent Antibody Technique; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D039902:Multipotent Stem Cells / Q000378:metabolism / Q000648:ultrastructure; D022022:Nuclear Pore / Q000378:metabolism*; D028861:Nuclear Pore Complex Proteins / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D009928:Organ Specificity; D038081:Organogenesis / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D014781:Viscera / Q000196:embryology* / Q000378:metabolism / Q000648:ultrastructure
D008562:Membrane Glycoproteins; D028861:Nuclear Pore Complex Proteins; D009687:Nuclear Proteins; C512902:Nup210 protein, mouse; D012333:RNA, Messenger