Published 10 April 2006. doi:10.1083/jcb.200511149
The Rockefeller University Press, 0021-9525 $8.00
JCB, Volume 173, Number 1, 83-93
Lamina-associated polypeptide 2
regulates cell cycle progression and differentiation via the retinoblastomaE2F pathway
Daniela Dorner1,
Sylvia Vlcek1,
Nicole Foeger1,
Andreas Gajewski1,
Christian Makolm1,
Josef Gotzmann1,
Christopher J. Hutchison2, and
Roland Foisner1
1 Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, A-1030 Vienna, Austria
2 Department of Biological Sciences, University of Durham, Durham DH1 3HP, United Kingdom
Correspondence to Roland Foisner: roland.foisner{at}meduniwien.ac.at
Lamina-associated polypeptide (LAP) 2
is a nonmembrane-bound LAP2 isoform that forms complexes with nucleoplasmic A-type lamins. In this study, we show that the overexpression of LAP2
in fibroblasts reduced proliferation and delayed entry into the cell cycle from a G0 arrest. In contrast, stable down-regulation of LAP2
by RNA interference accelerated proliferation and interfered with cell cycle exit upon serum starvation. The LAP2
-linked cell cycle phenotype is mediated by the retinoblastoma (Rb) protein because the LAP2
COOH terminus directly bound Rb, and overexpressed LAP2
inhibited E2F/Rb-dependent reporter gene activity in G1 phase in an Rb-dependent manner. Furthermore, LAP2
associated with promoter sequences in endogenous E2F/Rb-dependent target genes in vivo and negatively affected their expression. In addition, the expression of LAP2
in proliferating preadipocytes caused the accumulation of hypophosphorylated Rb, which is reminiscent of noncycling cells, and initiated partial differentiation into adipocytes. The effects of LAP2
on cell cycle progression and differentiation may be highly relevant for the cell- and tissue-specific phenotypes observed in laminopathic diseases.
Abbreviations used in this paper: LAP, lamina-associated polypeptide; LEM, LAP2emerinMAN1; MEF, mouse embryonic fibroblast; PPAR
, peroxisome proliferatoractivated receptor
; Rb, retinoblastoma; shRNA, short hairpin RNA; T3, triiodothyronine; TKO, triple knockout.

CiteULike
Complore
Connotea
Del.icio.us
Digg
Facebook
Reddit
Technorati
Twitter What's this?
This article has been cited by other articles:
-
Andres, V., Gonzalez, J. M.
(2009). Role of A-type lamins in signaling, transcription, and chromatin organization. JCB
187: 945-957
[Abstract]
[Full Text]
-
Tilgner, K., Wojciechowicz, K., Jahoda, C., Hutchison, C., Markiewicz, E.
(2009). Dynamic complexes of A-type lamins and emerin influence adipogenic capacity of the cell via nucleocytoplasmic distribution of {beta}-catenin. J. Cell Sci.
122: 401-413
[Abstract]
[Full Text]
-
Dechat, T., Pfleghaar, K., Sengupta, K., Shimi, T., Shumaker, D. K., Solimando, L., Goldman, R. D.
(2008). Nuclear lamins: major factors in the structural organization and function of the nucleus and chromatin. Genes Dev.
22: 832-853
[Abstract]
[Full Text]
-
Tsuchiya, Y.
(2008). Till Disassembly Do Us Part: A Happy Marriage of Nuclear Envelope and Chromatin. J Biochem
143: 155-161
[Abstract]
[Full Text]
-
Haraguchi, T., Koujin, T., Osakada, H., Kojidani, T., Mori, C., Masuda, H., Hiraoka, Y.
(2007). Nuclear localization of barrier-to-autointegration factor is correlated with progression of S phase in human cells. J. Cell Sci.
120: 1967-1977
[Abstract]
[Full Text]
-
Snyers, L., Vlcek, S., Dechat, T., Skegro, D., Korbei, B., Gajewski, A., Mayans, O., Schofer, C., Foisner, R.
(2007). Lamina-associated Polypeptide 2-{alpha} Forms Homo-trimers via Its C Terminus, and Oligomerization Is Unaffected by a Disease-causing Mutation. J. Biol. Chem.
282: 6308-6315
[Abstract]
[Full Text]
-
Naetar, N., Hutter, S., Dorner, D., Dechat, T., Korbei, B., Gotzmann, J., Beug, H., Foisner, R.
(2007). LAP2{alpha}-binding protein LINT-25 is a novel chromatin-associated protein involved in cell cycle exit. J. Cell Sci.
120: 737-747
[Abstract]
[Full Text]
-
Pekovic, V., Harborth, J., Broers, J. L.V., Ramaekers, F. C.S., van Engelen, B., Lammens, M., von Zglinicki, T., Foisner, R., Hutchison, C., Markiewicz, E.
(2007). Nucleoplasmic LAP2{alpha}-lamin A complexes are required to maintain a proliferative state in human fibroblasts. JCB
176: 163-172
[Abstract]
[Full Text]
-
(2006). Papers of Note. Sci Aging Knowl Environ
2006: nw8-nw8
[Full Text]