Τίτλος:
Modulation of DNA conformations through the formation of alternative
high-order HU-DNA complexes
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
HU is an abundant, highly conserved protein associated with the
bacterial chromosome. It belongs to a small class of proteins that
includes the eukaryotic proteins TBP, SRY, HMG-I and LEF-I, which bind
to DNA non-specifically at the minor groove. HU plays important roles as
an accessory architectural factor in a variety of bacterial cellular
processes such as DNA compaction, replication, transposition,
recombination and gene regulation. In an attempt to unravel the role
this protein plays in shaping nucleoid structure, we have carried out
fluorescence resonance energy transfer measurements of HU-DNA
oligonucleotide complexes, both at the ensemble and single-pair levels.
Our results provide direct experimental evidence for concerted DNA
bending by HU, and the abrogation of this effect at HU to DNA ratios
above about one HU dimer per 10-12 bp. These findings support a model in
which a number of HU molecules form an ordered helical scaffold with DNA
lying in the periphery. The abrogation of these nucleosome-like
structures for high HU to DNA ratios suggests a unique role for HU in
the dynamic modulation of bacterial nucleoid structure. (C) 2004
Elsevier Ltd. All rights reserved.
Συγγραφείς:
Sagi, D
Friedman, N
Vorgias, C
Oppenheim, AB
Stavans, J
Περιοδικό:
JOURNAL OF MOLECULAR BIOLOGY
Εκδότης:
ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
Λέξεις-κλειδιά:
histone-like proteins; HU-DNA interactions; FRET; DNA bending; single
molecule
DOI:
10.1016/j.jmb.2004.06.023
