title: Evaluation of cyclin D1 expression and its subcellular distribution in mouse tissues.
abstract: Cyclin D1 is a key cell-cycle regulatory protein required for the cell to progress through G1 to S phase. We have shown by Western blot analysis that cyclin D1 has a wide distribution in adult mouse tissues, with its level of expression being tissue-dependent. Immunohistochemistry has also shown that cyclin D1 may be present in the cytoplasm, in the nucleus or in both these cell compartments: cytoplasmic staining was observed in both proliferating cells (e.g. kidney, intestine, stomach and salivary gland) and in the non-dividing cells (the mature neurons of adult brain), while nuclear staining was seen in the neurons of the embryonic nervous system. Immunoelectron microscopy results indicate that, in tissues where cyclin D1 is present in both compartments (e.g. intestinal enterocytes), it may move via nuclear pores from the nucleus to the cytoplasm, and vice versa. The findings as a whole suggest that cyclin D1 may play multiple roles within specific tissues, probably by interacting with different substrates, and that its transit between nuclear and cytoplasmic compartments may help maintain cell homeostasis.
authors.affiliation: Department of Evolutive and Comparative Biology, University of Naples Federico II, Naples, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: De Falco
authors.forename: Valentina
authors.initials: V
authors.lastname: Fedele
authors.forename: Luca
authors.initials: L
authors.lastname: De Luca
authors.forename: Roberta
authors.initials: R
authors.lastname: Penta
authors.forename: Giuliano
authors.initials: G
authors.lastname: Cottone
authors.forename: Ivan
authors.initials: I
authors.lastname: Cavallotti
authors.forename: Vincenza
authors.initials: V
authors.lastname: Laforgia
authors.forename: Antonio
authors.initials: A
authors.lastname: De Luca
mesh_terms: D000818:Animals; D001692:Biological Transport; D001921:Brain; D002453:Cell Cycle; D002467:Cell Nucleus / Q000737:chemistry*; D019938:Cyclin D1 / Q000032:analysis*; D003593:Cytoplasm / Q000737:chemistry*; D004847:Epithelial Cells / Q000737:chemistry*; D015151:Immunoblotting / Q000379:methods; D007150:Immunohistochemistry / Q000379:methods; D007422:Intestines / Q000737:chemistry; D007684:Kidney Tubules / Q000737:chemistry; D008168:Lung / Q000737:chemistry; D051379:Mice; D016253:Microscopy, Immunoelectron; D009474:Neurons / Q000737:chemistry; D012469:Salivary Glands / Q000737:chemistry; D013270:Stomach / Q000737:chemistry
chemical_list: D019938:Cyclin D1