Um nur mal eine aktuelle Veröffentlichung im Kontext der Aneuploidie-Theorie anzusprechen
und damit aufzuzeigen, dass wir wirklich die alten Schlachtordungen verlassen sollten
(also hier:
Wenn deine Ploidie nicht stimmt, hast du schlechte Karten;
wenn deine Ploidie aber stimmt, wirst du nie Probleme haben -
s. Dr. Bliemeister in dem bisher unwidersprochen gebliebenenen BPS-Magazin-Artikel),
hier der Abstract 1079 des gegenwärtig ablaufenden Treffens der Amerikanischen Society für Zell-Biologie in San Francisco:
1079
Interphase fission maintains genomic integrity after failure of cytokinesis in human cells.
A. Choudhary1, R. Lera1, M. Martowicz1, J. Laffin2, B. Weaver3, M. E. Burkard1;
1Medicine, University of Wisconsin, Madison, WI,
2Wisconsin State Laboratory of Hygiene, University of Wisconsin, Madison, WI,
3Cell and Regenerative Medicine, University of Wisconsin, Madison, WI
The century-old Boveri hypothesis predicts that failure of cytokinesis leads to aberrant cell
divisions, aneuploidy, and cancer. We used modern single-cell techniques to investigate the
fate of human epithelial cells after failed cytokinesis. To do this, we established a uniform
population of binucleate interphase RPE1 cells that had previously segregated chromosomes
(karyokinesis) but failed to divide into daughters (failed cytokinesis). After minimizing effects of
DNA damage, we found a third of binucleate cells generate viable progeny. Strikingly, the
majority of the progeny are euploid, with a karyotype that matches the parental line, and only a
small fraction are near tetraploid. We performed confirmatory experiments that unambiguously
demonstrate that euploid colonies are derived from single binucleate cells. To elucidate the
mechanism of this process, we performed timelapse videomicroscopy. This revealed that
binucleate cells can execute cytoplasmic fission to segregate nuclei without intervening mitosis.
This fission echoes a primitive adhesion-dependent process reported in lower organisms such
as Dictyostelia. Using fluorescent Cdt1, we demonstrate that the fission occurs during the G1
phase. The fission event does not require canonical components required for cytokinesis,
demonstrating a distinct mechanism. Similar results were found in other human epithelial cell
types including MCF10a breast epithelial cells and HCT116 colorectal cancer cells. Interphase
fission can explain previous reports that polyploid multinucleate hepatocytes can resolve to
euploid hepatocytes. We conclude that human cells have a failsafe mechanism to maintain
euploidy in the face of cytokinesis failure, making subsequent aneuploidy less frequent than
envisioned by Boveri.
human cells have a failsafe mechanism = also ein Fehlerbehebungs-Programm o.ä. - sprich,
wenns Probleme bei der Zellteilung gibt und dann die Kern/-Chromosom-Situation bei den neuen Zellen nicht stimmt,
kann das in der Folge ausgeglichen werden und "Euploidy" wieder hergestellt werden, was zu weniger Aneuploidie führt als von Boveri noch angenommen.
Aber bis jetzt hat sich ja leider keiner der DNA-Zytometriker auf eine Debatte von Boveri & Co. eingelassen - vielleicht macht es ja Udo?
und damit aufzuzeigen, dass wir wirklich die alten Schlachtordungen verlassen sollten
(also hier:
Wenn deine Ploidie nicht stimmt, hast du schlechte Karten;
wenn deine Ploidie aber stimmt, wirst du nie Probleme haben -
s. Dr. Bliemeister in dem bisher unwidersprochen gebliebenenen BPS-Magazin-Artikel),
hier der Abstract 1079 des gegenwärtig ablaufenden Treffens der Amerikanischen Society für Zell-Biologie in San Francisco:
1079
Interphase fission maintains genomic integrity after failure of cytokinesis in human cells.
A. Choudhary1, R. Lera1, M. Martowicz1, J. Laffin2, B. Weaver3, M. E. Burkard1;
1Medicine, University of Wisconsin, Madison, WI,
2Wisconsin State Laboratory of Hygiene, University of Wisconsin, Madison, WI,
3Cell and Regenerative Medicine, University of Wisconsin, Madison, WI
The century-old Boveri hypothesis predicts that failure of cytokinesis leads to aberrant cell
divisions, aneuploidy, and cancer. We used modern single-cell techniques to investigate the
fate of human epithelial cells after failed cytokinesis. To do this, we established a uniform
population of binucleate interphase RPE1 cells that had previously segregated chromosomes
(karyokinesis) but failed to divide into daughters (failed cytokinesis). After minimizing effects of
DNA damage, we found a third of binucleate cells generate viable progeny. Strikingly, the
majority of the progeny are euploid, with a karyotype that matches the parental line, and only a
small fraction are near tetraploid. We performed confirmatory experiments that unambiguously
demonstrate that euploid colonies are derived from single binucleate cells. To elucidate the
mechanism of this process, we performed timelapse videomicroscopy. This revealed that
binucleate cells can execute cytoplasmic fission to segregate nuclei without intervening mitosis.
This fission echoes a primitive adhesion-dependent process reported in lower organisms such
as Dictyostelia. Using fluorescent Cdt1, we demonstrate that the fission occurs during the G1
phase. The fission event does not require canonical components required for cytokinesis,
demonstrating a distinct mechanism. Similar results were found in other human epithelial cell
types including MCF10a breast epithelial cells and HCT116 colorectal cancer cells. Interphase
fission can explain previous reports that polyploid multinucleate hepatocytes can resolve to
euploid hepatocytes. We conclude that human cells have a failsafe mechanism to maintain
euploidy in the face of cytokinesis failure, making subsequent aneuploidy less frequent than
envisioned by Boveri.
human cells have a failsafe mechanism = also ein Fehlerbehebungs-Programm o.ä. - sprich,
wenns Probleme bei der Zellteilung gibt und dann die Kern/-Chromosom-Situation bei den neuen Zellen nicht stimmt,
kann das in der Folge ausgeglichen werden und "Euploidy" wieder hergestellt werden, was zu weniger Aneuploidie führt als von Boveri noch angenommen.
Aber bis jetzt hat sich ja leider keiner der DNA-Zytometriker auf eine Debatte von Boveri & Co. eingelassen - vielleicht macht es ja Udo?
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