PMID- 15833996
OWN - NLM
STAT- MEDLINE
DCOM- 20051031
LR  - 20181113
IS  - 0006-3495 (Print)
IS  - 1542-0086 (Electronic)
IS  - 0006-3495 (Linking)
VI  - 89
IP  - 1
DP  - 2005 Jul
TI  - Dual binding modes for an HMG domain from human HMGB2 on DNA.
PG  - 353-64
AB  - High mobility group B (HMGB) proteins contain two HMG box domains known to bind 
      without sequence specificity into the DNA minor groove, slightly intercalating 
      between basepairs and producing a strong bend in the DNA backbone. We use optical 
      tweezers to measure the forces required to stretch single DNA molecules. 
      Parameters describing DNA flexibility, including contour length and persistence 
      length, are revealed. In the presence of nanomolar concentrations of isolated HMG 
      box A from HMGB2, DNA shows a decrease in its persistence length, where the 
      protein induces an average DNA bend angle of 114 +/- 21 degrees for 50 mM Na+, 
      and 87 +/- 9 degrees for 100 mM Na+. The DNA contour length increases from 0.341 
      +/- 0.003 to 0.397 +/- 0.012 nm per basepair, independent of salt concentration. 
      In 50 mM Na+, the protein does not unbind even at high DNA extension, whereas in 
      100 mM Na+, the protein appears to unbind only below concentrations of 2 nM. 
      These observations support a flexible hinge model for noncooperative HMG binding 
      at low protein concentrations. However, at higher protein concentrations, a 
      cooperative filament mode is observed instead of the hinge binding. This mode may 
      be uniquely characterized by this high-force optical tweezers experiment.
FAU - McCauley, Micah
AU  - McCauley M
AD  - Department of Physics and Center for Interdisciplinary Research on Complex 
      Systems, Northeastern University, Boston, Massachusetts 02115, USA.
FAU - Hardwidge, Philip R
AU  - Hardwidge PR
FAU - Maher, L James 3rd
AU  - Maher LJ 3rd
FAU - Williams, Mark C
AU  - Williams MC
LA  - eng
GR  - R01 GM054411/GM/NIGMS NIH HHS/United States
GR  - R01 GM072462/GM/NIGMS NIH HHS/United States
GR  - GM072462/GM/NIGMS NIH HHS/United States
GR  - GM54411/GM/NIGMS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, N.I.H., Extramural
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PT  - Research Support, U.S. Gov't, P.H.S.
DEP - 20050415
PL  - United States
TA  - Biophys J
JT  - Biophysical journal
JID - 0370626
RN  - 0 (HMGB2 Protein)
RN  - 0 (Polymers)
RN  - 9007-49-2 (DNA)
RN  - 9NEZ333N27 (Sodium)
SB  - IM
MH  - Animals
MH  - Biophysics/*methods
MH  - DNA/chemistry
MH  - Dose-Response Relationship, Drug
MH  - Drosophila
MH  - Escherichia coli/metabolism
MH  - HMGB2 Protein/*chemistry/metabolism
MH  - Magnetic Resonance Spectroscopy
MH  - Models, Statistical
MH  - Polymers/chemistry
MH  - Protein Binding
MH  - Protein Structure, Tertiary
MH  - Rats
MH  - Sodium/chemistry
PMC - PMC1366535
EDAT- 2005/04/19 09:00
MHDA- 2005/11/01 09:00
PMCR- 2006/07/01
CRDT- 2005/04/19 09:00
PHST- 2005/04/19 09:00 [pubmed]
PHST- 2005/11/01 09:00 [medline]
PHST- 2005/04/19 09:00 [entrez]
PHST- 2006/07/01 00:00 [pmc-release]
AID - S0006-3495(05)72685-0 [pii]
AID - 52068 [pii]
AID - 10.1529/biophysj.104.052068 [doi]
PST - ppublish
SO  - Biophys J. 2005 Jul;89(1):353-64. doi: 10.1529/biophysj.104.052068. Epub 2005 Apr 
      15.