Distinct functions of the unique C terminus of LAP2α in cell proliferation and nuclear assembly

被引:45
作者
Vlcek, S [1 ]
Korbei, B [1 ]
Foisner, R [1 ]
机构
[1] Univ Vienna, Vienna Bioctr, Dept Biochem & Mol Cell Biol, A-1030 Vienna, Austria
关键词
D O I
10.1074/jbc.M200048200
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The non-membrane-bound lamina-associated polypeptide 2 isoform, LAP2alpha, forms nucleoskeletal structures with A-type lamins and interacts with chromosomes in a cell cycle-dependent manner. LAP2alpha contains a LEM (LAP2, emerin, and MAN1) domain in the constant N terminus that binds to chromosomal barrier-to-autointegration factor, and a C-terminal unique region that is essential for chromosome binding. Here we show that C-terminal LAP2alpha fragment efficiently bound to mitotic chromosomes and inhibited assembly of endogenous LAP2alpha, nuclear membranes, and lamins A/C in in vitro nuclear assembly assays. Full-length recombinant LAP2alpha, which bound to chromosomes, and N-terminal fragment, which did not bind, had no effect on assembly. This suggested an essential role for the LAP2alpha C terminus in chromosome association and for the N-terminal LEM domain in subsequent assembly stages. In vivo analysis upon transient expression of GFP-tagged LAP2alpha fragments confirmed that, unlike the N-terminal fragment, the C-terminal fragment was able to bind to chromosomes during mitosis, if expressed weakly. At higher expression levels, C-terminal LAP2alpha fragment and full-length protein led to cell cycle arrest in interphase and apoptosis, as shown by fluorescence-activated cell sorter analysis, time lapse microscopy, and BrdUrd incorporation assays. These data indicated distinct functions of LAP2alpha in cell cycle progression during interphase and in nuclear reassembly during mitosis.
引用
收藏
页码:18898 / 18907
页数:10
相关论文
共 64 条
  • [1] The characterization and localization of the mouse thymopoietin lamina-associated polypeptide 2 gene and its alternatively spliced products
    Berger, R
    Theodor, L
    Shoham, J
    Gokkel, E
    BrokSimoni, F
    Avraham, KB
    Copeland, NG
    Jenkins, NA
    Rechavi, G
    Simon, AJ
    [J]. GENOME RESEARCH, 1996, 6 (05) : 361 - 370
  • [2] Bonne G, 2000, ANN NEUROL, V48, P170, DOI 10.1002/1531-8249(200008)48:2<170::AID-ANA6>3.0.CO
  • [3] 2-J
  • [4] BRIDGER JM, 1993, J CELL SCI, V104, P297
  • [5] Broers JLV, 1999, J CELL SCI, V112, P3463
  • [6] Buendia B, 1999, J CELL SCI, V112, P1743
  • [7] A CELL FREE SYSTEM TO STUDY REASSEMBLY OF THE NUCLEAR-ENVELOPE AT THE END OF MITOSIS
    BURKE, B
    GERACE, L
    [J]. CELL, 1986, 44 (04) : 639 - 652
  • [8] Lamins and apoptosis: A two-way street?
    Burke, B
    [J]. JOURNAL OF CELL BIOLOGY, 2001, 153 (03) : F5 - F7
  • [9] Solution structure of the constant region of nuclear envelope protein LAP2 reveals two LEM-domain structures: one binds BAF and the other binds DNA
    Cai, ML
    Huang, Y
    Ghirlando, R
    Wilson, KL
    Craigie, R
    Clore, GM
    [J]. EMBO JOURNAL, 2001, 20 (16) : 4399 - 4407
  • [10] Translocation of C. elegans CED-4 to nuclear membranes during programmed cell death
    Chen, FL
    Hersh, BM
    Conradt, B
    Zhou, Z
    Riemer, D
    Gruenbaum, Y
    Horvitz, HR
    [J]. SCIENCE, 2000, 287 (5457) : 1485 - 1489