title: Knockdown of dystrophin Dp71 impairs PC12 cells cycle: localization in the spindle and cytokinesis structures implies a role for Dp71 in cell division.
abstract: The function of dystrophin Dp71 in neuronal cells remains to be established. Previously, we revealed the involvement of this protein in both nerve growth factor (NGF)-induced neuronal differentiation and cell adhesion by isolation and characterization of PC12 neuronal cells with depleted levels of Dp71. In this work, a novel phenotype of Dp71-knockdown cells was characterized, which is their delayed growth rate. Cell cycle analyses revealed an altered behavior of Dp71-depleted cells, which consists of a delay in G0/G1 transition and an increase in apoptosis during nocodazole-induced mitotic arrest. Dp71 associates with lamin B1 and β-dystroglycan, proteins involved in aspects of the cell division cycle; therefore, we compared the distribution of Dp71 with that of lamin B1 and β-dystroglycan in PC12 cells at mitosis and cytokinesis by means of immunofluorescence and confocal microscopy analysis. All of these three proteins exhibited a similar immunostaining pattern, localized at mitotic spindle, cleavage furrow, and midbody. It is noteworthy that a drastic decreased staining in mitotic spindle, cleavage furrow, and midbody was observed for both lamin B1 and β-dystroglycan in Dp71-depleted cells. Furthermore, we demonstrated the interaction of Dp71 with lamin B1 in PC12 cells by immunoprecipitation and pull-down assays, and importantly, we revealed that knockdown of Dp71 expression caused a marked reduction in lamin B1 levels and altered localization of the nuclear envelope protein emerin. Our data indicate that Dp71 is a component of the mitotic spindle and cytokinesis multi-protein apparatuses that might modulate the cell division cycle by affecting lamin B1 and β-dystroglycan levels.
authors: Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del IPN (CINVESTAV-IPN), México Distrito Federal, México.
authors: Marcela
authors: M
authors: Villarreal-Silva
authors: Federico
authors: F
authors: Centeno-Cruz
authors: Rocío
authors: R
authors: Suárez-Sánchez
authors: Efraín
authors: E
authors: Garrido
authors: Bulmaro
authors: B
authors: Cisneros
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D048749:Cytokinesis / Q000187:drug effects; D049030:Dystroglycans / Q000378:metabolism; D016189:Dystrophin / Q000235:genetics* / Q000378:metabolism; D016193:G1 Phase / Q000187:drug effects; D055785:Gene Knockdown Techniques; D034921:Lamin Type B / Q000378:metabolism; D008938:Mitosis / Q000187:drug effects; D015739:Nocodazole / Q000494:pharmacology; D016716:PC12 Cells; D021381:Protein Transport / Q000187:drug effects; D051381:Rats; D016196:S Phase / Q000187:drug effects; D008941:Spindle Apparatus / Q000187:drug effects / Q000378:metabolism*
chemical_list: D016189:Dystrophin; D034921:Lamin Type B; C085339:apo-dystrophin 1; D049030:Dystroglycans; D015739:Nocodazole