Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.6.4.4 (kinesin)
 5,033 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The correct localization of myosin II to the equatorial cortex is crucial for proper cell division. Here, we examine a collection of genes that cause defects in cytokinesis and reveal with live cell imaging two distinct phases of myosin II localization. Three genes in the rho1 signaling pathway, pebble (a Rho guanidine nucleotide exchange factor), rho1, and rho kinase, are required for the initial recruitment of myosin II to the equatorial cortex. This initial localization mechanism does not require F-actin or the two components of the centralspindlin complex, the mitotic kinesin pavarotti/MKLP1 and racGAP50c/CYK-4. However, F-actin, the centralspindlin complex, formin (diaphanous), and profilin (chickadee) are required to stably maintain myosin II at the furrow. In the absence of these latter genes, myosin II delocalizes from the equatorial cortex and undergoes highly dynamic appearances and disappearances around the entire cell cortex, sometimes associated with abnormal contractions or blebbing. Our findings support a model in which a rho kinase-dependent event, possibly myosin II regulatory light chain phosphorylation, is required for the initial recruitment to the furrow, whereas the assembly of parallel, unbranched actin filaments, generated by formin-mediated actin nucleation, is required for maintaining myosin II exclusively at the equatorial cortex.
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PMID:Distinct pathways control recruitment and maintenance of myosin II at the cleavage furrow during cytokinesis. 1617 42

The tumor suppressor protein adenomatous polyposis coli (APC) is a multifunctional protein with a well characterized role in the Wnt signal transduction pathway and roles in cytoskeletal regulation and cell polarity. The soluble pool of APC protein in colon epithelial tumor cells exists in two distinct complexes fractionating at approximately 20S and approximately 60S in size. The 20S complex contains components of the beta-catenin destruction complex and probably functions in the Wnt pathway. In this study, we characterized the molecular nature of the 60S APC- containing complex by examining known potential binding partners of APC. 60S APC did not contain EB1 or diaphanous, proteins that have been reported to interact with APC and are implicated in microtubule plus end stabilization. Nor did the two other microtubule associated proteins, MAP4 or KAP3, which is thought to link APC to kinesin motor proteins, associate with the 60S complex. Minor fractions of alpha-tubulin, gamma-tubulin and IQGAP1, a Rac1 and CDC42 effector that interacts with APC, specifically associated with APC in the 60S fraction. We propose that 60S APC is a discrete high molecular weight complex with a novel function in cytoskeletal regulation in epithelial cells apart from its well established role in targeting catenin destruction or its proposed role in microtubule plus end stabilization.
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PMID:Characterization of a 60S complex of the adenomatous polyposis coli tumor suppressor protein. 1712 24