Open AccessReverse engineering of force integration during mitosis in the Drosophila embryo
Author(s) -
Wollman Roy,
CivelekogluScholey Gul,
Scholey Jonathan M,
Mogilner Alex
Publication year - 2008
Publication title -
molecular systems biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 8.523
H-Index - 148
ISSN - 1744-4292
DOI - 10.1038/msb.2008.23
Subject(s) - prometaphase , biology , mitosis , anaphase , spindle apparatus , microtubule , molecular motor , kinesin , dynein , microbiology and biotechnology , mechanism (biology) , chromosome segregation , spindle pole body , computational biology , genetics , chromosome , cell division , physics , gene , quantum mechanics , cell
The mitotic spindle is a complex macromolecular machine that coordinates accurate chromosome segregation. The spindle accomplishes its function using forces generated by microtubules (MTs) and multiple molecular motors, but how these forces are integrated remains unclear, since the temporal activation profiles and the mechanical characteristics of the relevant motors are largely unknown. Here, we developed a computational search algorithm that uses experimental measurements to ‘reverse engineer’ molecular mechanical machines. Our algorithm uses measurements of length time series for wild‐type and experimentally perturbed spindles to identify mechanistic models for coordination of the mitotic force generators in Drosophila embryo spindles. The search eliminated thousands of possible models and identified six distinct strategies for MT–motor integration that agree with available data. Many features of these six predicted strategies are conserved, including a persistent kinesin‐5‐driven sliding filament mechanism combined with the anaphase B‐specific inhibition of a kinesin‐13 MT depolymerase on spindle poles. Such conserved features allow predictions of force–velocity characteristics and activation–deactivation profiles of key mitotic motors. Identified differences among the six predicted strategies regarding the mechanisms of prometaphase and anaphase spindle elongation suggest future experiments.