Dystrophin Dp71 is critical for stability of the DAPs in the nucleus of PC12 cells.
We have adopted the PC12 cell line as in vitro cell model for studying Dp71 function in neuronal cells. These cells express a cytoplasmic (Dp71f) and a nuclear (Dp71d) isoform of Dp71 as well as various dystrophin-associated proteins (DAPs). In this study, we revealed by confocal microscopy analysis and Western blotting evaluation of cell fractions the presence of different DAPs (beta-dystroglycan, beta-dystrobrevin, epsilon-sarcoglycan and gamma1-syntrophin) in the nucleus of PC12 cells. Furthermore, we established by immunoprecipitation assays that Dp71d and the DAPs form a dystrophin-associated protein complex (DAPC) in the nucleus. Interestingly, depletion of Dp71 by antisense treatment (antisense-Dp71 cells) provoked a drastic reduction of nuclear DAPs, which indicates that Dp71d is critical for DAPs stability within the nucleus. Although Up71, the utrophin gene product homologous to Dp71, exhibited increased expression in the antisense-Dp71 cells, its scarce nuclear levels makes unlikely that could compensate for Dp71 nuclear deficiency.
Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del IPN, Avenida Instituto Politécnico Nacional 2508, Apartado Postal 14-740, CP 07360, Mexico, DF, Mexico.
Marcela
M
Villarreal-Silva
Rocío
R
Suárez-Sánchez
Rafael
R
Rodríguez-Muñoz
Dominique
D
Mornet
Bulmaro
B
Cisneros
D000818:Animals; D015153:Blotting, Western; D002467:Cell Nucleus / Q000378:metabolism*; D016189:Dystrophin / Q000172:deficiency / Q000502:physiology*; D049029:Dystrophin-Associated Proteins / Q000378:metabolism*; D007150:Immunohistochemistry; D047468:Immunoprecipitation; D018613:Microscopy, Confocal; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D016716:PC12 Cells; D051381:Rats; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism
D016189:Dystrophin; D049029:Dystrophin-Associated Proteins; D016376:Oligonucleotides, Antisense; C085339:apo-dystrophin 1