title: Localization, dynamics, and function of survivin revealed by expression of functional survivinDsRed fusion proteins in the living cell.
abstract: Survivin, a member of the inhibitor of apoptosis protein family, has attracted growing attention due to its expression in various tumors and its potential application in tumor therapy. However, its subcellular localization and function have remained controversial: Recent studies revealed that survivin is localized at the mitotic spindle, binds caspases, and could thus protect cells from apoptosis. The cell cycle-dependent expression of survivin and its antiapoptotic function led to the hypothesis that survivin connects the cell cycle with apoptosis, thus providing a death switch for the termination of defective mitosis. In other studies, survivin was detected at kinetochores, cleavage furrow, and midbody, localizations being characteristic for chromosomal passenger proteins. These proteins are involved in cytokinesis as inferred from the observation that RNA interference and expression of mutant proteins led to cytokinesis defects without an increase in apoptosis. To remedy these discrepancies, we analyzed the localizations of a survivinDsRed fusion protein in HeLa cells by using confocal laser scanning microscopy and time-lapse video imaging. SurvivinDsRed was excluded from the interphase nucleus and was detected in centrosomes and at kinetochores. It dissociated from chromosomes at the anaphase/telophase transition and accumulated at the ends of polar microtubuli where it was immediately condensed to the midbody. Overexpression of both survivinDsRed and of a phosphorylation-defective mutant conferred resistance against apoptosis-inducing reagents, but only the overexpressed mutant protein caused an aberrant cytokinesis. These data characterize in detail the dynamics of survivin in vertebrate cells and confirm that survivin represents a chromosomal passenger protein.
authors.affiliation: Institute of Immunology, Medical Faculty Carl Gustav Carus, Technical University Dresden, 01307 Dresden, Germany. temme@rcs.urz.tu-dresden.de
authors.forename: Achim
authors.initials: A
authors.lastname: Temme
authors.forename: Michael
authors.initials: M
authors.lastname: Rieger
authors.forename: Friedemann
authors.initials: F
authors.lastname: Reber
authors.forename: Dirk
authors.initials: D
authors.lastname: Lindemann
authors.forename: Bernd
authors.initials: B
authors.lastname: Weigle
authors.forename: Petra
authors.initials: P
authors.lastname: Diestelkoetter-Bachert
authors.forename: Gerhard
authors.initials: G
authors.lastname: Ehninger
authors.forename: Masaaki
authors.initials: M
authors.lastname: Tatsuka
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Terada
authors.forename: Ernst Peter
authors.initials: EP
authors.lastname: Rieber
mesh_terms: D017209:Apoptosis / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D006367:HeLa Cells; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D018386:Kinetochores / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism*; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism; D009154:Mutation; D009363:Neoplasm Proteins; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D000077022:Survivin; D000097573:Red Fluorescent Protein
chemical_list: D051034:Inhibitor of Apoptosis Proteins; D008164:Luminescent Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D011993:Recombinant Fusion Proteins; D000077022:Survivin; D000097573:Red Fluorescent Protein; C107489:BIRC5 protein, human