Abstract
The 175-kDa myosin-11 from Nicotiana tabacum (Nt(175kDa)myosin-11) is exceptional in its mechanical activity as it is the fastest known processive actin-based motor, moving 10 times faster than the structurally related class 5 myosins. Although this ability might be essential for long-range organelle transport within larger plant cells, the kinetic features underlying the fast processive movement of Nt(175kDa)myosin-11 still remain unexplored. To address this, we generated a single-headed motor domain construct and carried out a detailed kinetic analysis. The data demonstrate that Nt(175kDa)myosin-11 is a high duty ratio motor, which remains associated with actin most of its enzymatic cycle. However, different from other processive myosins that establish a high duty ratio on the basis of a rate-limiting ADP-release step, Nt(175kDa)myosin-11 achieves a high duty ratio by a prolonged duration of the ATP-induced isomerization of the actin-bound states and ADP release kinetics, both of which in terms of the corresponding time constants approach the total ATPase cycle time. Molecular modeling predicts that variations in the charge distribution of the actin binding interface might contribute to the thermodynamic fine-tuning of the kinetics of this myosin. Our study unravels a new type of a high duty ratio motor and provides important insights into the molecular mechanism of processive movement of higher plant myosins.
| Original language | English |
|---|---|
| Pages (from-to) | 81-94 |
| Number of pages | 14 |
| Journal | FASEB Journal |
| Volume | 29 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - 2015 Jan 1 |
| Externally published | Yes |
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Keywords
- homology modeling
- molecular mechanics
- plant
- processivity
ASJC Scopus subject areas
- Medicine(all)
Cite this
Kinetic mechanism of Nicotiana tabacum myosin-11 defines a new type of a processive motor. / Diensthuber, Ralph P.; Tominaga, Motoki; Preller, Matthias; Hartmann, Falk K.; Orii, Hidefumi; Chizhov, Igor; Oiwa, Kazuhiro; Tsiavaliaris, Georgios.
In: FASEB Journal, Vol. 29, No. 1, 01.01.2015, p. 81-94.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Kinetic mechanism of Nicotiana tabacum myosin-11 defines a new type of a processive motor
AU - Diensthuber, Ralph P.
AU - Tominaga, Motoki
AU - Preller, Matthias
AU - Hartmann, Falk K.
AU - Orii, Hidefumi
AU - Chizhov, Igor
AU - Oiwa, Kazuhiro
AU - Tsiavaliaris, Georgios
PY - 2015/1/1
Y1 - 2015/1/1
N2 - The 175-kDa myosin-11 from Nicotiana tabacum (Nt(175kDa)myosin-11) is exceptional in its mechanical activity as it is the fastest known processive actin-based motor, moving 10 times faster than the structurally related class 5 myosins. Although this ability might be essential for long-range organelle transport within larger plant cells, the kinetic features underlying the fast processive movement of Nt(175kDa)myosin-11 still remain unexplored. To address this, we generated a single-headed motor domain construct and carried out a detailed kinetic analysis. The data demonstrate that Nt(175kDa)myosin-11 is a high duty ratio motor, which remains associated with actin most of its enzymatic cycle. However, different from other processive myosins that establish a high duty ratio on the basis of a rate-limiting ADP-release step, Nt(175kDa)myosin-11 achieves a high duty ratio by a prolonged duration of the ATP-induced isomerization of the actin-bound states and ADP release kinetics, both of which in terms of the corresponding time constants approach the total ATPase cycle time. Molecular modeling predicts that variations in the charge distribution of the actin binding interface might contribute to the thermodynamic fine-tuning of the kinetics of this myosin. Our study unravels a new type of a high duty ratio motor and provides important insights into the molecular mechanism of processive movement of higher plant myosins.
AB - The 175-kDa myosin-11 from Nicotiana tabacum (Nt(175kDa)myosin-11) is exceptional in its mechanical activity as it is the fastest known processive actin-based motor, moving 10 times faster than the structurally related class 5 myosins. Although this ability might be essential for long-range organelle transport within larger plant cells, the kinetic features underlying the fast processive movement of Nt(175kDa)myosin-11 still remain unexplored. To address this, we generated a single-headed motor domain construct and carried out a detailed kinetic analysis. The data demonstrate that Nt(175kDa)myosin-11 is a high duty ratio motor, which remains associated with actin most of its enzymatic cycle. However, different from other processive myosins that establish a high duty ratio on the basis of a rate-limiting ADP-release step, Nt(175kDa)myosin-11 achieves a high duty ratio by a prolonged duration of the ATP-induced isomerization of the actin-bound states and ADP release kinetics, both of which in terms of the corresponding time constants approach the total ATPase cycle time. Molecular modeling predicts that variations in the charge distribution of the actin binding interface might contribute to the thermodynamic fine-tuning of the kinetics of this myosin. Our study unravels a new type of a high duty ratio motor and provides important insights into the molecular mechanism of processive movement of higher plant myosins.
KW - homology modeling
KW - molecular mechanics
KW - plant
KW - processivity
UR - http://www.scopus.com/inward/record.url?scp=84928702978&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84928702978&partnerID=8YFLogxK
U2 - 10.1096/fj.14-254763
DO - 10.1096/fj.14-254763
M3 - Article
C2 - 25326536
AN - SCOPUS:84928702978
VL - 29
SP - 81
EP - 94
JO - FASEB Journal
JF - FASEB Journal
SN - 0892-6638
IS - 1
ER -