TY - JOUR
T1 - The activation mode of the mechanosensitive ion channel, MscL, by lysophosphatidylcholine differs from tension-induced gating
AU - Mukherjee, N.
AU - Jose, M.D.
AU - Birkner, J.P.
AU - Walko, M.
AU - Ingólfsson, H.I.
AU - Dimitrova, A.
AU - Arnarez, C.
AU - Marrink, S.J.
AU - Koçer, A.
PY - 2014
Y1 - 2014
N2 - One of the best-studied mechanosensitive channels is the mechanosensitive channel of large conductance (MscL). MscL senses tension in the membrane evoked by an osmotic down shock and directly couples it to large conformational changes leading to the opening of the channel. Spectroscopic techniques offer unique possibilities to monitor these conformational changes if it were possible to generate tension in the lipid bilayer, the native environment of MscL, during the measurements. To this end, asymmetric insertion of L-α-lysophosphatidylcholine (LPC) into the lipid bilayer has been effective; however, how LPC activates MscL is not fully understood. Here, the effects of LPC on tension-sensitive mutants of a bacterial MscL and on MscL homologs with different tension sensitivities are reported, leading to the conclusion that the mode of action of LPC is different from that of applied tension. Our results imply that LPC shifts the free energy of gating by interfering with MscL-membrane coupling. Furthermore, we demonstrate that the fine-tuned addition of LPC can be used for controlled activation of MscL in spectroscopic studies.—Mukherjee, N., Jose, M. D., Birkner, J. P., Walko, M., Ingólfsson, H. I., Dimitrova, A., Arnarez, C., Marrink, S. J., Koçer, A., The activation mode of the mechanosensitive ion channel, MscL, by lysophosphatidylcholine differs from tension-induced gating. FASEB J. 28, 4292–4302 (2014). www.fasebj.org
AB - One of the best-studied mechanosensitive channels is the mechanosensitive channel of large conductance (MscL). MscL senses tension in the membrane evoked by an osmotic down shock and directly couples it to large conformational changes leading to the opening of the channel. Spectroscopic techniques offer unique possibilities to monitor these conformational changes if it were possible to generate tension in the lipid bilayer, the native environment of MscL, during the measurements. To this end, asymmetric insertion of L-α-lysophosphatidylcholine (LPC) into the lipid bilayer has been effective; however, how LPC activates MscL is not fully understood. Here, the effects of LPC on tension-sensitive mutants of a bacterial MscL and on MscL homologs with different tension sensitivities are reported, leading to the conclusion that the mode of action of LPC is different from that of applied tension. Our results imply that LPC shifts the free energy of gating by interfering with MscL-membrane coupling. Furthermore, we demonstrate that the fine-tuned addition of LPC can be used for controlled activation of MscL in spectroscopic studies.—Mukherjee, N., Jose, M. D., Birkner, J. P., Walko, M., Ingólfsson, H. I., Dimitrova, A., Arnarez, C., Marrink, S. J., Koçer, A., The activation mode of the mechanosensitive ion channel, MscL, by lysophosphatidylcholine differs from tension-induced gating. FASEB J. 28, 4292–4302 (2014). www.fasebj.org
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84907707955&partnerID=MN8TOARS
U2 - 10.1096/fj.14-251579
DO - 10.1096/fj.14-251579
M3 - Article
SN - 0892-6638
VL - 28
SP - 4292
EP - 4302
JO - FASEB journal
JF - FASEB journal
IS - 10
ER -