| Id |
Subject |
Object |
Predicate |
Lexical cue |
| T1 |
148-373 |
DRI_Background |
denotes |
Myosin II is the force-generating motor for cytokinesis, and although it is accepted that myosin contractility is greatest at the cell equator, the temporal and spatial cues that direct equatorial contractility are not known. |
| T2 |
374-686 |
DRI_Background |
denotes |
Dividing sea urchin eggs were placed under compression to study myosin II-based contractile dynamics, and cells manipulated in this manner underwent an abrupt, global increase in cortical contractility concomitant with the metaphase-anaphase transition, followed by a brief relaxation and the onset of furrowing. |
| T3 |
687-878 |
DRI_Background |
denotes |
Prefurrow cortical contractility both preceded and was independent of astral microtubule elongation, suggesting that the initial activation of myosin II preceded cleavage plane specification. |
| T4 |
879-1037 |
DRI_Challenge |
denotes |
The initial rise in contractility required myosin light chain kinase but not Rho-kinase, but both signaling pathways were required for successful cytokinesis. |
| T5 |
1038-1244 |
DRI_Approach |
denotes |
Last, mobilization of intracellular calcium during metaphase induced a contractile response, suggesting that calcium transients may be partially responsible for the timing of this initial contractile event. |
| T6 |
1245-1503 |
DRI_Background |
denotes |
Together, these findings suggest that myosin II-based contractility is initiated at the metaphase-anaphase transition by Ca2+-dependent myosin light chain kinase (MLCK) activity and is maintained through cytokinesis by both MLCK- and Rho-dependent signaling. |
| T7 |
1504-1668 |
DRI_Outcome |
denotes |
Moreover, the signals that initiate myosin II contractility respond to specific cell cycle transitions independently of the microtubule-dependent cleavage stimulus. |
