title: The retinoblastoma family: twins or distant cousins?
abstract: The destiny of a cell--whether it undergoes division, differentiation or death--results from an intricate balance of many regulators, including oncoproteins, tumor-suppressor proteins and cell-cycle-associated proteins. One of the better-studied tumor suppressors is the retinoblastoma protein, known as pRb or p105. Two recently identified proteins, pRb2/p130 and p107, show structural and functional similarities to pRb, and these proteins and their orthologs make up the retinoblastoma (Rb) family. Members of the family have been found in animals and plants, and a related protein is known in the alga Chlamydomonas. Members of the Rb family are bound and inactivated by viral proteins and, in turn, bind cellular transcription factors and repress their function, and can also form complexes with cyclins and cyclin-dependent kinases and with histone deacetylases. They are found in the nucleus and their subnuclear localization depends on binding to the nuclear matrix. Members of the family form part of a signal-transduction pathway called the Rb pathway, which is important in cell-cycle regulation and have roles in growth suppression, differentiation and apoptosis in different organisms and cell types.
authors.affiliation: Sbarro Institute for Cancer Research and Molecular Medicine, College of Science and Technologies, Temple University, Philadelphia, PA 19122, USA.
authors.forename: Pier Paolo
authors.initials: PP
authors.lastname: Claudio
authors.forename: Tiziana
authors.initials: T
authors.lastname: Tonini
authors.forename: Antonio
authors.initials: A
authors.lastname: Giordano
mesh_terms: D000818:Animals; D017209:Apoptosis; D002454:Cell Differentiation; D002874:Chromosome Mapping; D019143:Evolution, Molecular; D016161:Genes, Retinoblastoma; D006801:Humans; D051379:Mice; D018919:Neovascularization, Physiologic; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology; D010750:Phosphoproteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology; D010802:Phylogeny; D010944:Plants / Q000235:genetics; D011506:Proteins; D051381:Rats; D016160:Retinoblastoma Protein / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D050720:Retinoblastoma-Like Protein p107; D050717:Retinoblastoma-Like Protein p130
chemical_list: D009687:Nuclear Proteins; D010750:Phosphoproteins; D011506:Proteins; C493844:RBL1 protein, human; C493837:RBL2 protein, human; C489485:Rbl1 protein, mouse; C493838:Rbl2 protein, mouse; C493839:Rbl2 protein, rat; D016160:Retinoblastoma Protein; D050720:Retinoblastoma-Like Protein p107; D050717:Retinoblastoma-Like Protein p130