Location, degree, and direction of DNA bending associated with the Hin recombinational enhancer sequence and Fis-enhancer complex.
نویسندگان
چکیده
The Fis protein of Escherichia coli and Salmonella typhimurium stimulates several site-specific DNA recombination reactions, as well as transcription of a number of genes. Fis binds to a 15-bp core recognition sequence and induces DNA bending. Mutations in Fis which alter its ability to bend DNA have been shown to reduce the stimulatory activity of Fis in both site-specific recombination and transcription systems. To examine the role of DNA bending in the activity of the Fis-recombinational enhancer complex in Hin-mediated site-specific DNA inversion, we have determined the locations, degrees, and directions of DNA bends associated with the recombinational enhancer and the Fis-enhancer complex. Circular-permutation assays demonstrated that a sequence-directed DNA bend is associated with the Fis binding sites in the proximal and distal domains of the recombinational enhancer. Binding of Fis to its core recognition sequence significantly increases the degree of DNA bending associated with the proximal and distal domains. The degree of DNA bending induced by Fis binding depended on the DNA sequences flanking the core Fis binding site, with angles ranging from 42 to 69 degrees. Phasing analyses indicate that both the sequence-directed and the Fis-induced DNA bends associated with the proximal and distal domains face the minor groove of the DNA helix at the center of the Fis binding site. The positions and directions of DNA bends associated with the Fis-recombinational complex support a direct role for Fis-induced DNA bending in assembly of the active invertasome.
منابع مشابه
Isolation of the gene encoding the Hin recombinational enhancer binding protein.
In vitro DNA inversion mediated by the protein Hin requires the presence of a recombinational enhancer sequence located in cis relative to the recombination sites and a protein, Fis, which binds to the enhancer. We have cloned and determined the primary sequence of the gene encoding Fis. The deduced amino acid sequence of Fis indicates that the protein is 98 amino acids long and contains a pote...
متن کاملMultiple interfaces between a serine recombinase and an enhancer control site-specific DNA inversion
Serine recombinases are often tightly controlled by elaborate, topologically-defined, nucleoprotein complexes. Hin is a member of the DNA invertase subclass of serine recombinases that are regulated by a remote recombinational enhancer element containing two binding sites for the protein Fis. Two Hin dimers bound to specific recombination sites associate with the Fis-bound enhancer by DNA loopi...
متن کاملThe Hin dimer interface is critical for Fis-mediated activation of the catalytic steps of site-specific DNA inversion
BACKGROUND Hin is a member of an extended family of site-specific recombinases--the DNA invertase/resolvase family--that catalyze inversion or deletion of DNA. DNA inversion by Hin occurs between two recombination sites and requires the regulatory protein Fis, which associates with a cis-acting recombinational enhancer sequence. Hin recombinase dimers bind to the two recombination sites and ass...
متن کاملEffect of DNA superhelicity and bound proteins on mechanistic aspects of the Hin-mediated and Fis-enhanced inversion.
Using a recently developed inhomogeneous, macroscopic model for long DNA bound to proteins, we examine topological and geometric aspects of DNA/protein structures and dynamics on various stages of the Hin inversion pathway. This biological reaction involves exchange of DNA in a synaptic complex that brings together several DNA sites bound to Hin dimers as well as Fis enhancers. Brownian dynamic...
متن کاملStepwise dissection of the Hin-catalyzed recombination reaction from synapsis to resolution.
The Hin DNA invertase promotes a site-specific DNA recombination reaction in the Salmonella chromosome. The native Hin reaction exhibits overwhelming selectivity for promoting inversions between appropriately oriented recombination sites and requires the Fis regulatory protein, a recombinational enhancer, and a supercoiled DNA substrate. Here, we report a robust recombination reaction employing...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of bacteriology
دوره 179 15 شماره
صفحات -
تاریخ انتشار 1997