Mutagenesis of apobec-1 complementation factor reveals distinct domains that modulate RNA binding, protein-protein interaction with apobec-1, and complementation of C to U RNA-editing activity

被引:42
作者
Blanc, V
Henderson, JO
Kennedy, S
Davidson, NO
机构
[1] Washington Univ, Sch Med, Div Gastroenterol, Dept Internal Med, St Louis, MO 63110 USA
[2] Washington Univ, Sch Med, Dept Mol Biol & Pharmacol, St Louis, MO 63110 USA
关键词
D O I
10.1074/jbc.M107654200
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
C to U editing of apolipoprotein B (apoB) RNA requires a multicomponent holoenzyme complex in which minimal constituents include apobec-1 and apobec-1 complementation factor (ACF). We have examined the predicted functional domains in ACF in binding apoB RNA, interaction with apobec-1, and complementation of RNA editing. We demonstrate that apoB RNA binding and apobec-1-interacting domains are defined by two partially overlapping regions containing the NH2-terminal RNA recognition motifs of ACF. Both apoB RNA binding and apobec-1 interaction are required for editing complementation activity. ACF is a nuclear protein that upon cotransfection with apobec-1 results in nuclear colocalization and redistribution of apobec-1 from the cytoplasm. ACF constructs with deletions or mutations in the putative nuclear localization signal (NLS) still localize in the nucleus of transfected cells but do not colocalize with apobec-1, the latter remaining predominantly cytoplasmic. These observations suggest that the putative NLS motif in ACF is not responsible for its nucleo-cytoplasmic trafficking. By contrast, protein-protein interaction is important for the nuclear import of apobec-1. Taken together, these data suggest that functional complementation of C to U RNA editing by apobec-1 involves the NH2-terminal 380 residues of ACF.
引用
收藏
页码:46386 / 46393
页数:8
相关论文
共 45 条
[1]   APOBEC-1, THE CATALYTIC SUBUNIT OF THE MAMMALIAN APOLIPOPROTEIN-B MESSENGER-RNA EDITING ENZYME, IS A NOVEL RNA-BINDING PROTEIN [J].
ANANT, S ;
MACGINNITIE, AJ ;
DAVIDSON, NO .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1995, 270 (24) :14762-14767
[2]   An AU-rich sequence element (UUUN[A/U]U) downstream of the edited C in apolipoprotein B mRNA is a high-affinity binding site for Apobec-1:: Binding of Apobec-1 to this motif in the 3′ untranslated region of c-myc increases mRNA stability [J].
Anant, S ;
Davidson, NO .
MOLECULAR AND CELLULAR BIOLOGY, 2000, 20 (06) :1982-1992
[3]   Molecular mechanisms of apolipoprotein B mRNA editing [J].
Anant, S ;
Davidson, NO .
CURRENT OPINION IN LIPIDOLOGY, 2001, 12 (02) :159-165
[4]   3 DISTINCT RNA SEQUENCE ELEMENTS ARE REQUIRED FOR EFFICIENT APOLIPOPROTEIN-B (APO-B) RNA EDITING INVITRO [J].
BACKUS, JW ;
SMITH, HC .
NUCLEIC ACIDS RESEARCH, 1992, 20 (22) :6007-6014
[5]   RNA editing and hypermutation by adenosine deamination [J].
Bass, BL .
TRENDS IN BIOCHEMICAL SCIENCES, 1997, 22 (05) :157-162
[6]   (O)over-cap | identification of GRY-RBP as an apolipoprotein B RNA-binding protein that interacts with both apobec-1 and apobec-1 complementation factor to modulate C to U editing [J].
Blanc, V ;
Navaratnam, N ;
Henderson, JO ;
Anant, S ;
Kennedy, S ;
Jarmuz, A ;
Scott, J ;
Davidson, NO .
JOURNAL OF BIOLOGICAL CHEMISTRY, 2001, 276 (13) :10272-10283
[7]   CONSERVED STRUCTURES AND DIVERSITY OF FUNCTIONS OF RNA-BINDING PROTEINS [J].
BURD, CG ;
DREYFUSS, G .
SCIENCE, 1994, 265 (5172) :615-621
[8]   APOLIPOPROTEIN B-48 IS THE PRODUCT OF A MESSENGER-RNA WITH AN ORGAN-SPECIFIC IN-FRAME STOP CODON [J].
CHEN, SH ;
HABIB, G ;
YANG, CY ;
GU, ZW ;
LEE, BR ;
WENG, SA ;
SILBERMAN, SR ;
CAI, SJ ;
DESLYPERE, JP ;
ROSSENEU, M ;
GOTTO, AM ;
LI, WH ;
CHAN, L .
SCIENCE, 1987, 238 (4825) :363-366
[9]   Apolipoprotein B: mRNA editing, lipoprotein assembly, and presecretory degradation [J].
Davidson, NO ;
Shelness, GS .
ANNUAL REVIEW OF NUTRITION, 2000, 20 :169-+
[10]   SITE-DIRECTED MUTAGENESIS OF VIRTUALLY ANY PLASMID BY ELIMINATING A UNIQUE SITE [J].
DENG, WP ;
NICKOLOFF, JA .
ANALYTICAL BIOCHEMISTRY, 1992, 200 (01) :81-88