A nuclear matrix protein related to intermediate filaments proteins is a member of the complex binding alphoid DNA in vitro.
A complex of three proteins (of 80, 70, 58 kDa-p80, p70, and p58, respectively) with the ability to bind alphoid DNA (alpha-satDNA) was revealed by gel mobility shift assay (GMSA) in human nuclear matrix. The probes of the alpha-satDNA bound in the GMSA with the greatest specificity, but the complex was capable of binding human satellite 3 fragment. According to ion exchange and affinity chromatography, the complex includes two DNA-binding proteins, p70 and p80, and a non-DNA-binding one, p58, which enhances the specificity of binding to the alpha-satDNA. GMSA, SDS-PAGE and immunoblotting showed that the lamins, as well as constitutive centromeric proteins (CENP-A, CENP-B, CENP-C, CENP-G), were not incorporated into the complex. It was demonstrated by immunoprecipitation assay that p70 and, probably p58, share a common antigen determinant with the rod domain of intermediate filaments (IF) proteins. The results obtained indicate that the nuclear matrix contains at least one IF-related protein that is able to bind specifically to alpha-satDNA in vitro and that this protein is distinct from the lamins.
Enukashvily
N I
NI
Institute of Cytology RAS, Tikhoretsky, 4, St. Petersburg, 194064, Russia. natella@ivm.stud.pu.ru
Lobov
I B
IB
Kukalev
A
A
Podgornaya
O I
OI
D000818:Animals; D002453:Cell Cycle; D002458:Cell Fractionation; D002845:Chromatography; D004276:DNA, Satellite / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000032:analysis* / Q000276:immunology / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D006168:Guinea Pigs; D006801:Humans; D015151:Immunoblotting; D007381:Intermediate Filament Proteins / Q000032:analysis; D008970:Molecular Weight; D015530:Nuclear Matrix / Q000737:chemistry* / Q000276:immunology; D009687:Nuclear Proteins / Q000032:analysis* / Q000276:immunology / Q000378:metabolism
D004276:DNA, Satellite; D004268:DNA-Binding Proteins; D007381:Intermediate Filament Proteins; D009687:Nuclear Proteins