Silencing of Nuclear Mitotic Apparatus protein (NuMA) accelerates the apoptotic disintegration of the nucleus.
Apoptosis
; 15(8): 936-45, 2010 Aug.
Article
in En
| MEDLINE
| ID: mdl-20467816
ABSTRACT
One main feature of apoptosis is the sequential degradation of the nuclear structure, including the fragmentation of chromatin and caspase-mediated cleavage of various nuclear proteins. Among these proteins is the Nuclear Mitotic Apparatus protein (NuMA) which plays a specific role in the organization of the mitotic spindle. The exact function of NuMA in the interphase nucleus is unknown, but a number of reports have suggested that it may play a role in chromatin organization and/or gene expression. Here we show that upon cleavage in apoptotic cells, the N-terminal cleavage fragment of NuMA is solubilized while the C-terminal fragment remains associated with the condensed chromatin. Using pancaspase inhibitor z-VAD-fmk and caspase-3 deficient MCF-7 cells, we further show that the solubilization is dependent on caspase-mediated cleavage of NuMA. Finally, the silencing of NuMA by RNAi accelerated nuclear breakdown in apoptotic MCF-7 cells. These results suggest that NuMA may provide structural support in the interphase nucleus by contributing to the organization of chromatin.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Cell Nucleus
/
Apoptosis
/
Gene Silencing
/
Antigens, Nuclear
/
Nuclear Matrix-Associated Proteins
Limits:
Humans
Language:
En
Journal:
Apoptosis
Year:
2010
Document type:
Article
Affiliation country:
Finlandia