ESCHERICHIA-COLI SEQA PROTEIN BINDS ORIC IN 2 DIFFERENT METHYL-MODULATED REACTIONS APPROPRIATE TO ITS ROLES IN DNA-REPLICATION INITIATION AND ORIGIN SEQUESTRATION

被引：245

作者：

SLATER, S ^{[1
]}

WOLD, S ^{[1
]}

LU, M ^{[1
]}

BOYE, E ^{[1
]}

SKARSTAD, K ^{[1
]}

KLECKNER, N ^{[1
]}

机构：

[1] INST CANC RES,DEPT BIOPHYS,N-0310 MONTEBELLO,NORWAY

来源：

CELL | 1995年 / 82卷 / 06期

关键词：

D O I：

10.1016/0092-8674(95)90272-4

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 seqA gene negatively modulates replication initiation at the E. coli origin, oriC. seqA is also essential for sequestration, which acts at oriC and the dnaA promoter to ensure that replication initiation occurs exactly once per chromosome per cell cycle. Initiation is promoted by full methylation of GATC sites clustered in oriC; sequestration is specific to the hemimethylated forms generated by replication, SeqA protein purification and DNA binding are described. SeqA interacts with fully methylated oriC strongly and specifically, This reaction requires multiple molecules of SeqA and determinants throughout oriC, including segments involved in open complex formation. SeqA interacts more strongly with hemimethylated DNA; in this case, oriC and non-oriC sequences are bound similarly. Also, binding of hemimethylated oriC by membrane fractions is due to SeqA. Direct interaction of SeqA protein with the replication origin is likely to be involved in both replication initiation and sequestration.

引用

页码：927 / 936

页数：10

共 35 条

[1]

Bachmann BJ, 1987, ESCHERICHIA COLI SAL, P1190

[2]

BAKER TA, 1902, ANNU REV GENET, V26, P447

[3] HU, THE MAJOR HISTONE-LIKE PROTEIN OF ESCHERICHIA-COLI, MODULATES THE BINDING OF IHF TO ORIC [J].