TY - JOUR
T1 - Charge movement of a voltage-sensitive fluorescent protein
AU - Villalba-Galea, Carlos A.
AU - Sandtner, Walter
AU - Dimitrov, Dimitar
AU - Mutoh, Hiroki
AU - Knöpfel, Thomas
AU - Bezanilla, Francisco
PY - 2009/1/21
Y1 - 2009/1/21
N2 - The N-terminus of Ciona intestinalis (Ci-VSP) is a voltage-sensing domain (VSD) controlling the activity of a phosphatase domain on the C terminus. By replacing the phosphatase domain with a tandem of fluorescent proteins, CFP and YFP, a family of fluorescence resonance energy transfer-based, genetically encoded voltage-sensing fluorescent protein (VSFP) was created. VSFP2.3, one of the latest versions of this family, showed large changes in YFP emission upon changes in membrane potential with CFP excitation when expressed in Xenopus laevis oocytes. The time course of the fluorescence has two components: the fast component correlates with the time course of sensing current produced by the charge movement, while the slow component is at least one order-of-magnitude slower than the sensing current. This suggests that the tandem of fluorescent proteins reports a secondary conformational transition of the VSD which resembles the relaxation of the VSD of Ci-VSP described in detail for the Ci-VSP. This observation indicates that the relaxation of the VSD of VSFP2.3 is a global conformational change that encompasses the entire S4 segment.
AB - The N-terminus of Ciona intestinalis (Ci-VSP) is a voltage-sensing domain (VSD) controlling the activity of a phosphatase domain on the C terminus. By replacing the phosphatase domain with a tandem of fluorescent proteins, CFP and YFP, a family of fluorescence resonance energy transfer-based, genetically encoded voltage-sensing fluorescent protein (VSFP) was created. VSFP2.3, one of the latest versions of this family, showed large changes in YFP emission upon changes in membrane potential with CFP excitation when expressed in Xenopus laevis oocytes. The time course of the fluorescence has two components: the fast component correlates with the time course of sensing current produced by the charge movement, while the slow component is at least one order-of-magnitude slower than the sensing current. This suggests that the tandem of fluorescent proteins reports a secondary conformational transition of the VSD which resembles the relaxation of the VSD of Ci-VSP described in detail for the Ci-VSP. This observation indicates that the relaxation of the VSD of VSFP2.3 is a global conformational change that encompasses the entire S4 segment.
UR - http://www.scopus.com/inward/record.url?scp=58849137606&partnerID=8YFLogxK
U2 - 10.1016/j.bpj.2008.11.003
DO - 10.1016/j.bpj.2008.11.003
M3 - Journal article
AN - SCOPUS:58849137606
SN - 0006-3495
VL - 96
SP - L19-L21
JO - Biophysical Journal
JF - Biophysical Journal
IS - 2
ER -
