TY - JOUR
T1 - Structural Insights of the DciA Helicase Loader in Its Relationship with DNA
AU - Cargemel, Claire
AU - Baconnais, Sonia
AU - Aumont-Nicaise, Magali
AU - Noiray, Magali
AU - Maurin, Lia
AU - Andreani, Jessica
AU - Walbott, Hélène
AU - Le Cam, Eric
AU - Ochsenbein, Françoise
AU - Marsin, Stéphanie
AU - Quevillon-Cheruel, Sophie
N1 - Publisher Copyright:
© 2023 by the authors.
PY - 2023/1/1
Y1 - 2023/1/1
N2 - DciA is the ancestral bacterial replicative helicase loader, punctually replaced during evolution by the DnaC/I loaders of phage origin. DnaC helps the helicase to load onto DNA by cracking open the hexameric ring, but the mechanism of loading by DciA remains unknown. We demonstrate by electron microscopy, nuclear magnetic resonance (NMR) spectroscopy, and biochemistry experiments that DciA, which folds into a KH-like domain, interacts with not only single-stranded but also double-stranded DNA, in an atypical mode. Some point mutations of the long α-helix 1 demonstrate its importance in the interaction of DciA for various DNA substrates mimicking single-stranded, double-stranded, and forked DNA. Some of these mutations also affect the loading of the helicase by DciA. We come to the hypothesis that DciA could be a DNA chaperone by intercalating itself between the two DNA strands to stabilize it. This work allows us to propose that the direct interaction of DciA with DNA could play a role in the loading mechanism of the helicase.
AB - DciA is the ancestral bacterial replicative helicase loader, punctually replaced during evolution by the DnaC/I loaders of phage origin. DnaC helps the helicase to load onto DNA by cracking open the hexameric ring, but the mechanism of loading by DciA remains unknown. We demonstrate by electron microscopy, nuclear magnetic resonance (NMR) spectroscopy, and biochemistry experiments that DciA, which folds into a KH-like domain, interacts with not only single-stranded but also double-stranded DNA, in an atypical mode. Some point mutations of the long α-helix 1 demonstrate its importance in the interaction of DciA for various DNA substrates mimicking single-stranded, double-stranded, and forked DNA. Some of these mutations also affect the loading of the helicase by DciA. We come to the hypothesis that DciA could be a DNA chaperone by intercalating itself between the two DNA strands to stabilize it. This work allows us to propose that the direct interaction of DciA with DNA could play a role in the loading mechanism of the helicase.
KW - DciA
KW - DNA interaction
KW - replicative helicase loading
KW - structural study
UR - http://www.scopus.com/inward/record.url?scp=85146812436&partnerID=8YFLogxK
U2 - 10.3390/ijms24021427
DO - 10.3390/ijms24021427
M3 - Article
C2 - 36674944
AN - SCOPUS:85146812436
SN - 1661-6596
VL - 24
JO - International Journal of Molecular Sciences
JF - International Journal of Molecular Sciences
IS - 2
M1 - 1427
ER -