A precise DNA bend angle is essential for the function of the phage φ29 transcriptional regulator

نویسندگان

  • Laura Pérez-Lago
  • Margarita Salas
  • Ana Camacho
چکیده

Bacteriophage phi29 protein p4 is essential for the regulation of the switch from early to late phage transcription. The protein binds to two regions of the phage genome located between the regulated promoters. Each region contains two inverted repeats separated by 1 bp. We used circular permutation assays to study the topology of the DNA upon binding of the protein and found that p4 induced the same extent of bending independent of the topology of the binding region. In addition, the results revealed that the p4-induced bending is not dependent on the affinity to the binding site but is intrinsic to p4 binding. Independent binding sites were identified through the characterization of the minimal sequence required for p4 binding. The protein has different affinity for each of its binding sites, with those overlapping the A2c and A2b promoter cores (sites 1 and 3), having the highest affinity. The functionality of the p4 binding sites and the contribution of p4-mediated promoter restructuring in transcription regulation is discussed.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

DNA-Binding Proteins Essential for Protein-Primed Bacteriophage Φ29 DNA Replication

Bacillus subtilis phage Φ29 has a linear, double-stranded DNA 19 kb long with an inverted terminal repeat of 6 nucleotides and a protein covalently linked to the 5' ends of the DNA. This protein, called terminal protein (TP), is the primer for the initiation of replication, a reaction catalyzed by the viral DNA polymerase at the two DNA ends. The DNA polymerase further elongates the nascent DNA...

متن کامل

Functional linkages between replication proteins of genes 1, 3 and 5 of Bacillus subtilis phage φ29.

Gene 1 product (gp1) of Bacillus subtilis phage φ29 has been shown to be involved in viral DNA replication in vivo, but the essential role is still unknown. As part of an ongoing effort to understand the role of gp1 in viral DNA replication, we investigated genetic interaction between gene 1 and other viral genes. Because φ29 mutants which do not produce functional gp1 show temperature-sensitiv...

متن کامل

Single-stranded DNA binding protein Gp5 of Bacillus subtilis phage Φ29 is required for viral DNA replication in growth-temperature dependent fashion.

In the absence of viral single-stranded DNA binding protein gp5, Bacillus subtilis phage φ29 failed to grow and to replicate its genome at 45 °C, while it grew and replicated normally at 30 °C and 42 °C. This indicates that gp5 is dispensable for φ29 DNA replication at 42 °C and lower temperatures.

متن کامل

Most mutant OccR proteins that are defective in positive control hold operator DNA in a locked high-angle bend.

OccR is a LysR-type transcriptional regulator of Agrobacterium tumefaciens that positively regulates the octopine catabolism operon of the Ti plasmid. Positive control of the occ genes occurs in response to octopine, a nutrient released from crown gall tumors. OccR also functions as an autorepressor in the presence or absence of octopine. OccR binds to a site between occQ and occR in the presen...

متن کامل

Laminar Flow Analysis in the Channel Bends

In this paper the laminar flow in the rectangular channel bends is simulated using numerical techniques. The turning angle of the channel bend and the area ratio of the channel cross-section are two important parameters to be examined. For flow simulation, the body fitted 3-D continuity and momentum equations are used and a body fitted general purpose code is developed. The existing results of ...

متن کامل

ذخیره 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 نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Nucleic Acids Research

دوره 33  شماره 

صفحات  -

تاریخ انتشار 2005