JBP1 and JBP2 are two distinct thymidine hydroxylases involved in J biosynthesis in genomic DNA of African trypanosomes

被引:65
作者
Cliffe, Laura J. [1 ]
Kieft, Rudo [1 ]
Southern, Timothy [1 ]
Birkeland, Shanda R. [1 ]
Marshall, Marion [1 ]
Sweeney, Kate [1 ]
Sabatini, Robert [1 ]
机构
[1] Univ Georgia, Dept Biochem & Mol Biol, Athens, GA 30602 USA
基金
美国国家卫生研究院;
关键词
D-GLUCOSYL-HYDROXYMETHYLURACIL; J-BINDING PROTEIN; MODIFIED BASE J; KINETOPLASTID PROTOZOANS; SWI2/SNF2-LIKE PROTEIN; RHODOTORULA-GLUTINIS; THYMINE HYDROXYLASE; GENE-EXPRESSION; BRUCEI; GLYCOSYLATION;
D O I
10.1093/nar/gkn1067
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
Genomic DNA of African trypanosomes contains a hypermodified thymidine residue termed base J (-d-glucosyl-HOMedU). This modified base is localized primarily to repetitive DNA, namely the telomeres, and is implicated in the regulation of antigenic variation. The base is synthesized in a two-step pathway. Initially, a thymidine residue in DNA is hydroxylated by a thymidine hydroxylase (TH). This intermediate (HOMedU) is then glucosylated to form base J. Two proteins involved in J synthesis, JBP1 (J binding protein 1) and JBP2, contain a putative TH domain related to the family of Fe-2/2-oxoglutarate-dependent hydroxylases. We have previously shown that mutations in the TH domain of JBP1 kill its ability to stimulate J synthesis. Here we show that mutation of key residues in the TH domain of JBP2 ablate its ability to induce de novo J synthesis. While the individual JBP1 null and JBP2 null trypanosomes have reduced J levels, the deletion of both JBP1 and JBP2 generates a cell line that completely lacks base J but still contains glucosyl-transferase activity. Reintroduction of JBP2 in the J-null trypanosome stimulates HOMedU formation and site-specific synthesis of base J. We conclude that JBP2 and JBP1 are the TH enzymes involved in J biosynthesis.
引用
收藏
页码:1452 / 1462
页数:11
相关论文
共 25 条
[1]   ACTIVATION OF TRYPANOSOME SURFACE GLYCOPROTEIN GENES INVOLVES A DUPLICATION-TRANSPOSITION LEADING TO AN ALTERED 3' END [J].
BERNARDS, A ;
VANDERPLOEG, LHT ;
FRASCH, ACC ;
BORST, P ;
BOOTHROYD, JC ;
COLEMAN, S ;
CROSS, GAM .
CELL, 1981, 27 (03) :497-505
[2]   Base J: Discovery, Biosynthesis, and Possible Functions [J].
Borst, Piet ;
Sabatini, Robert .
ANNUAL REVIEW OF MICROBIOLOGY, 2008, 62 :235-251
[3]   The modified base J is the target for a novel DNA-binding protein in kinetoplastid protozoans [J].
Cross, M ;
Kieft, R ;
Sabatini, R ;
Wilm, M ;
de Kort, M ;
van der Marel, GA ;
van Boom, JH ;
van Leeuwen, F ;
Borst, P .
EMBO JOURNAL, 1999, 18 (22) :6573-6581
[4]   J-binding protein increases the level and retention of the unusual base J in trypanosome DNA [J].
Cross, M ;
Kieft, R ;
Sabatini, R ;
Dirks-Mulder, A ;
Chaves, I ;
Borst, P .
MOLECULAR MICROBIOLOGY, 2002, 46 (01) :37-47
[5]   Regulation of trypanosome DNA glycosylation by a SWI2/SNF2-like protein [J].
DiPaolo, C ;
Kieft, R ;
Cross, M ;
Sabatini, R .
MOLECULAR CELL, 2005, 17 (03) :441-451
[6]   Formation of linear inverted repeat amplicons following targeting of an essential gene in Leishmania [J].
Genest, PA ;
ter Riet, B ;
Dumas, C ;
Papadopoulou, B ;
van Luenen, HGAM ;
Borst, P .
NUCLEIC ACIDS RESEARCH, 2005, 33 (05) :1699-1709
[7]   Repression of polymerase I-mediated gene expression at Trypanosoma brucei telomeres [J].
Glover, L ;
Horn, D .
EMBO REPORTS, 2006, 7 (01) :93-99
[8]   A NOVEL DNA NUCLEOTIDE IN TRYPANOSOMA-BRUCEI ONLY PRESENT IN THE MAMMALIAN PHASE OF THE LIFE-CYCLE [J].
GOMMERSAMPT, J ;
LUTGERINK, J ;
BORST, P .
NUCLEIC ACIDS RESEARCH, 1991, 19 (08) :1745-1751
[9]   O-glycoside orientation is an essential aspect of base J recognition by the kinetoplastid DNA-binding protein JBP1 [J].
Grover, Rajesh K. ;
Pond, Stephanie J. K. ;
Cui, Qizhi ;
Subramaniam, Prem ;
Case, David A. ;
Millar, David P. ;
Wentworth, Paul, Jr. .
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 2007, 46 (16) :2839-2843
[10]   Fe(II)/α-ketoglutarate-dependent hydroxylases and related enzymes [J].
Hausinger, RP .
CRITICAL REVIEWS IN BIOCHEMISTRY AND MOLECULAR BIOLOGY, 2004, 39 (01) :21-68