title: Cellular processes underlying maturation of P19 neurons: Changes in protein folding regimen and cytoskeleton organization.
abstract: Embryonal carcinoma P19 cells provide an ideal model to study molecular programs along differentiation. Upon induction by retinoic acid (RA), the cells undergo a program of differentiation that generates functioning neurons within 60 h. RA induced cells that were plated as sparse (1000 cells/mm(2)) or dense (4000 cells/mm(2)) cultures showed a marked difference in the culture morphology with the dense cultures exhibiting rapid maturation and accelerated neurite outgrowth. The protein expression levels of the sparse and dense cultures were compared 48 h following RA. Cell extracts were separated by 1-DE and 2-DE and differential expression (>four-fold) proteins were identified by MS. Here, we focus on 20 proteins associated with cytoskeletal regulation and stress-dependent protein refolding. The first group includes drebrin, cofilin, alpha-internexin, vimentin, and nestin. Among the proteins in the second group are subunits of the TCP-1, and several chaperones of the Hsp70 and Hsp90 families. We show that coordinated remodeling of the cytoskeleton and modulations in chaperone activity underlie the change in neurite extension rate. Furthermore, a proteomics-based analysis applied on P19 neurons demonstrated pathways underlying neuronal outgrowth, suggesting that a malfunction of such pathways leads to neuropathological conditions.
authors: Department of Biological Chemistry, Life Sciences Institute, The Hebrew University of Jerusalem, Jerusalem, Israel.
authors: Alex
authors: A
authors: Inberg
authors: Yoel
authors: Y
authors: Bogoch
authors: Yaniv
authors: Y
authors: Bledi
authors: Michal
authors: M
authors: Linial
mesh_terms: D000818:Animals; D018236:Carcinoma, Embryonal; D002454:Cell Differentiation / Q000502:physiology; D003598:Cytoskeletal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D003599:Cytoskeleton / Q000737:chemistry / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D013058:Mass Spectrometry; D051379:Mice; D008969:Molecular Sequence Data; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D017510:Protein Folding; D014212:Tretinoin / Q000494:pharmacology; D014407:Tumor Cells, Cultured
chemical_list: D003598:Cytoskeletal Proteins; D014212:Tretinoin