Midbody ring disposal by autophagy is a post-abscission event of cytokinesis (Nat Cell Biol, 2009, 11:65-70)

報告日期: 2009/03/20
報告時間: 16:00/16:50
報告學生: 吳珊瑩
講評老師: 沈孟儒


Midbody ring disposal by autophagy is a post-abscission event

of cytokinesis


Nat Cell Biol, 2009, 11(1):65-70


Speaker : 吳珊瑩

Commentator : 沈孟儒 老師 

Time :  2009.03.20 ( PM: 4:00~4:50)

Place :  Room 602


Cytokinesis is a fundamental process which results in division of a single cell into two daughter cells with identical genomic composition. At the end of cytokinesis, the dividing cells are connected by an intercellular bridge, which contains the midbody along with a circular structure of densely ubiquitylated, called midbody ring (MR). MR consists of microtubules and a high protein density area. In a poorly understood final step called abscission, MR disappeared from one of the daughter cells and how these large structures disappear remaining unknown. Membrane trafficking is required for late stages of cytokinesis. Autophagic process is also related with membrane trafficking, so the authors want to clarify whether autophagy is involved in cytokinesis. In this report, they observed that p62, a ubiquitin-binding protein linked to autophagy, contributes to MR disposal. They reveal that MR in the daughter cell is engulfed by the Atg8-positive vesicle called autophagosome and discarded by the autophagic process. These data suggest that autophagy is coupled to cytokinesis. In the cells of the patients with lysosome storage disorder (I-cell disease and Hurler syndrome), MR accumclation is significantly greater, compared to the control cells. Taken together, autophagy plays an important role in post-cytokinesis, especially in midbody ring elimination.


References :

1.   Eggert, U. S., Mitchison, T. J. & Field, C. M. Animal cytokinesis: from parts list to mechanisms. Annu. Rev. Biochem. 75, 543–566 (2006).

2.   Settembre, C. et al. A block of autophagy in lysosomal storage disorders. Hum. Mol. Genet. 17, 119–129 (2008).

3.   Mukai, A. et al. Dynamic regulation of ubiquitylation and deubiquitylation at the central spindle during cytokinesis. J. Cell Sci. 121, 1325–1333 (2008).