Evolution of self-transmissible genetic elements: replication mechanisms and control of phage-plasmids N15 and P4

Información del proyecto

Identificador del acuerdo de subvención: INTAS-96-1492

Proyecto cerrado

Fecha de inicio 1 Noviembre 1997

Fecha de finalización 31 Octubre 2000

Financiado con arreglo a

• International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993-

Coste total

Sin datos

Aportación de la UE

€ 60 000,00

Coordinado por

THE UNIVERSITY OF MILANO
Italy

Objetivo

The aim of this project is to analyse and compare from the evolutionary point of view the replication and regulatory mechanisms of two unusual self-replicating elements found in Escherichia coli, the phage-plasmids N15 and P4. N15 is a temperate phage that, as a prophage, replicates as a linear plasmid with covalently closed ends. P4 is an integrative plasmid that can exploit the morphogenetic functions of a "helper" virus such as P2. Specific objectives of this research proposal are: Mollar analysis of P4 immunity system. The P4 immunity factor is a processed antisense RNA that acts on complementary targets on a nascent transcript thus eliciting efficient transcription termination. The antisense RNA processing pathway and the mechanism of transcription termination will be analysed. This may lead to a better understanding of general mechanisms of transcription termination and RNA processing and degradation in bacteria. Completion of N15 genome sequencing and sequence analysis; analysis of N15 transcription pattern and gene expression control in the lytic and plasmid states. This will give a detailed physical, genetic and transcription map of the phage; will outline the overall N15 developmental strategies; will disclose specific regulatory switches that will be analysed in more detail.
Analysis of DNA replication from the two different origins identified in P4 and control of P4 replication in its different developmental stages.This will elucidate the mechanism of P4 copy number control via interaction between the P4 primase- helicase and the Cnr regulatory protein, and will define the role of the second origin of replication. Study of N15 replication in vivo and in vitro.
This research is aimed to dissect mollar mechanisms of plasmid and lytic replication, identify genes and ori sites, and establish an in vitro replication system for N15 replication. Due to their unique properties, both P4 and N15 appear to be evolutionary links between plasmids and viruses and may therefore provide exceptionally useful model systems for the study of virus, plasmid, and bacterial evolution. Moreover, a better understanding of N15 mollar properties could be exploited to develop new pliar vectors for cloning and for genetic manipulation of micro-organisms.

Programa(s)

• IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993-

Tema(s)

Datos no disponibles

Convocatoria de propuestas

Datos no disponibles

Régimen de financiación

Datos no disponibles

Coordinador

THE UNIVERSITY OF MILANO

• Aportación de la UE: Sin datos
• Dirección: Via Celoria 26 ; 20133 MILANO ; Italia
• Coste total: Sin datos

Participantes (3)

Bioengineering Center

Rusia

• Aportación de la UE: Sin datos
• Dirección: 117334 Moscow
• Coste total: Sin datos

Max-Planck-Institut fuer Molekulare Genetik

Alemania

• Aportación de la UE: Sin datos
• Dirección: 14195 Berlin
• Coste total: Sin datos

State Technical University

Rusia

• Aportación de la UE: Sin datos
• Dirección: 195251 Saint Petersburg
• Coste total: Sin datos