FUNCTION OF THE P86 SUBUNIT OF EUKARYOTIC INITIATION-FACTOR (ISO)4F AS A MICROTUBULE-ASSOCIATED PROTEIN IN PLANT-CELLS

被引:43
作者
BOKROS, CL
HUGDAHL, JD
KIM, HH
HANESWORTH, VR
VANHEERDEN, A
BROWNING, KS
MOREJOHN, LC
机构
[1] UNIV TEXAS, DEPT BOT, AUSTIN, TX 78713 USA
[2] UNIV TEXAS, DEPT BIOCHEM & CHEM, AUSTIN, TX 78713 USA
关键词
D O I
10.1073/pnas.92.15.7120
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
The isozyme form of eukaryotic initiation factor 4F [eIF-(iso)4F] from wheat germ is composed of a p28 subunit that binds the 7-methylguanine cap of mRNA and a p86 subunit having unknown function. The p86 subunit was found to have limited sequence similarity to a kinesin-like protein encoded by the katA gene of Arabidopsis thaliana. Native wheat germ eIF-(iso)4F and bacterially expressed p86 subunit and p86-p28 complex bound to taxol-stabilized maize microtubules (MTs) in vitro. Binding saturation occurred at 1 mol of p86 per 5-6 mol of polymerized tubulin dimer, demonstrating a substoichiometric interaction of p86 with MTs. No evidence was found for a direct interaction of the p28 subunit with MTs. Unlike kinesin, cosedimentation of eIF-(iso)4F with MTs was neither reduced by MgATP nor enhanced by adenosine 5'-[gamma-imido] triphosphate. Both p86 subunit and p86-p28 complex induced the bundling of MTs in vitro. The p86 subunit was immunolocalized to the cytosol in root maize cells and existed in three forms: fine particles, coarse particles, and linear patches. Many coarse particles and linear patches were colocalized or closely associated with cortical MT bundles in interphase cells. The results indicate that the p86 subunit of eIF-(iso) 4F is a MT-associated protein that may simultaneously link the translational machinery to the cytoskeleton and regulate MT disposition in plant cells.
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页码:7120 / 7124
页数:5
相关论文
共 48 条
  • [1] ALLEN ML, 1992, J BIOL CHEM, V267, P23232
  • [2] BALUSKA F, 1992, J CELL SCI, V103, P191
  • [3] MICROTUBULE-ASSOCIATED PROTEIN-1B - IDENTIFICATION OF A MAJOR COMPONENT OF THE NEURONAL CYTOSKELETON
    BLOOM, GS
    LUCA, FC
    VALLEE, RB
    [J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1985, 82 (16) : 5404 - 5408
  • [4] 10-NM FILAMENTS ARE INDUCED TO COLLAPSE IN LIVING CELLS MICROINJECTED WITH MONOCLONAL AND POLYCLONAL ANTIBODIES AGAINST TUBULIN
    BLOSE, SH
    MELTZER, DI
    FERAMISCO, JR
    [J]. JOURNAL OF CELL BIOLOGY, 1984, 98 (03) : 847 - 858
  • [5] CHARACTERIZATION OF THE REVERSIBLE TAXOL-INDUCED POLYMERIZATION OF PLANT TUBULIN INTO MICROTUBULES
    BOKROS, CL
    HUGDAHL, JD
    HANESWORTH, VR
    MURTHY, JV
    MOREJOHN, LC
    [J]. BIOCHEMISTRY, 1993, 32 (13) : 3437 - 3447
  • [6] BRADFORD MM, 1976, ANAL BIOCHEM, V72, P248, DOI 10.1016/0003-2697(76)90527-3
  • [7] BROWNING KS, 1992, J BIOL CHEM, V267, P10096
  • [8] BROWNING KS, 1990, J BIOL CHEM, V265, P17967
  • [9] MESSENGER-RNA IS TRANSLATED WHEN ASSOCIATED WITH THE CYTOSKELETAL FRAMEWORK IN NORMAL AND VSV-INFECTED HELA-CELLS
    CERVERA, M
    DREYFUSS, G
    PENMAN, S
    [J]. CELL, 1981, 23 (01) : 113 - 120
  • [10] CYTOSKELETON-BOUND POLYSOMES IN PLANTS .3. POLYSOME-CYTOSKELETON-MEMBRANE INTERACTIONS IN CORN ENDOSPERM
    DAVIES, E
    COMER, EC
    LIONBERGER, JM
    STANKOVIC, B
    ABE, S
    [J]. CELL BIOLOGY INTERNATIONAL, 1993, 17 (03) : 331 - 340