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conferenceseries
.com
Volume 7, Issue 5 (Suppl)
J Biotechnol Biomater
ISSN: 2155-952X JBTBM, an open access journal
Biotechnology 2017
November 13-14, 2017
November 13-14, 2017 Osaka, Japan
19
th
World Congress on
Biotechnology
Repetitive DNA unwinding mode of the
HIM-6
RecQ helicase
Byungchan Ahn
1
, Seoyun Choi
1
and Hajin Kim
2
1
University of Ulsan, South Korea
2
Ulsan National Institute of Science and Technology, South Korea
B
loom’s syndrome (BS) is caused by mutations in the BLM gene encoding the BLM helicase. The BLM protein contains a
conserved RecQ helicase domain and unwinds various DNA substrates including replication forks. Cells from BS patients
lack the BLM protein show defects in the response to replicative stress and contain a multitude of chromosomal aberrations.
A BLM homolog (
HIM-6
) has been identified in
C. elegans
based on its close homology to human BLM. Here, we used single-
molecule FRET technology to observe DNA unwinding in real time. Our results show that the
HIM-6
repetitively unwound a
long forked DNA depending on ATP concentration and resolved flap and D-loop DNA, all of which are intermediates in DNA
repair. Also, we found that
HIM-6
unwound at most 25 base pairs of duplex DNA in a speed of 28 nucleotides per second before
returning. Besides, repetitive unwinding mode of
HIM-6
was changed to unidirectional unwinding in the presence of RPA,
indicating that its unwinding mode can be modulated by partner proteins
in vivo
. This study can be used to search proteins
which would modulate a
HIM-6
unwinding mode on different DNA structures such as Holliday junction and G4-quadruplex.
Biography
Byungchan Ahn is a Professor of Department of Life Science, University of Ulsan, South Korea.
bbccahn@yahoo.comByungchan Ahn et al., J Biotechnol Biomater 2017, 7:5 (Suppl)
DOI: 10.4172/2155-952X-C1-083