title: Telomerase-negative immortalized human cells contain a novel type of promyelocytic leukemia (PML) body.
abstract: Telomerase-negative immortalized human cells maintain their telomeres by a mechanism known as alternative lengthening of telomeres (ALT). We report here that ALT cells contain a novel promyelocytic leukemia (PML) body (ALT-associated PML body, APB). APBs are large donut-shaped nuclear structures containing PML protein, telomeric DNA, and the telomere binding proteins human telomere repeat binding factors 1 and 2. Immunostaining showed that APBs also contain replication factor A, RAD51, and RAD52, proteins involved in DNA synthesis and recombination. During immortalization, APBs appeared at exactly the same time as activation of ALT. APBs were found in ALT tumors and cell lines but not in mortal cell strains or in telomerase-positive cell lines or tumors.
authors.affiliation: Children's Medical Research Institute, Westmead, Sydney, New South Wales, Australia.
authors.forename: T R
authors.initials: TR
authors.lastname: Yeager
authors.forename: A A
authors.initials: AA
authors.lastname: Neumann
authors.forename: A
authors.initials: A
authors.lastname: Englezou
authors.forename: L I
authors.initials: LI
authors.lastname: Huschtscha
authors.forename: J R
authors.initials: JR
authors.lastname: Noble
authors.forename: R R
authors.initials: RR
authors.lastname: Reddel
mesh_terms: D002449:Cell Aggregation; D002467:Cell Nucleus / Q000737:chemistry*; D004268:DNA-Binding Proteins / Q000032:analysis; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D009363:Neoplasm Proteins / Q000032:analysis*; D009369:Neoplasms / Q000737:chemistry / Q000235:genetics* / Q000648:ultrastructure; D009687:Nuclear Proteins; D000071156:Promyelocytic Leukemia Protein; D019098:Telomerase / Q000378:metabolism*; D035341:Telomeric Repeat Binding Protein 2; D014157:Transcription Factors / Q000032:analysis*; D014407:Tumor Cells, Cultured; D025521:Tumor Suppressor Proteins
chemical_list: D004268:DNA-Binding Proteins; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D000071156:Promyelocytic Leukemia Protein; D035341:Telomeric Repeat Binding Protein 2; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; C070576:PML protein, human; D019098:Telomerase