The Kinesin-like Calmodulin Binding Protein Is Differentially Involved in Cell Division

AUTOR(ES)

Vos, Jan W.

FONTE

American Society of Plant Physiologists

RESUMO

The kinesin-like calmodulin (CaM) binding protein (KCBP), a minus end–directed microtubule motor protein unique to plants, has been implicated in cell division. KCBP is negatively regulated by Ca2+ and CaM, and antibodies raised against the CaM binding region inhibit CaM binding to KCBP in vitro; therefore, these antibodies can be used to activate KCBP constitutively. Injection of these antibodies into Tradescantia virginiana stamen hair cells during late prophase induces breakdown of the nuclear envelope within 2 to 10 min and leads the cell into prometaphase. However, mitosis is arrested, and the cell does not progress into anaphase. Injection of antibodies later during cell division has no effect on anaphase transition but causes aberrant phragmoplast formation and delays the completion of cytokinesis by ∼15 min. These effects are achieved without any apparent degradation of the microtubule cytoskeleton. We propose that during nuclear envelope breakdown and anaphase, activated KCBP promotes the formation of a converging bipolar spindle by sliding and bundling microtubules. During metaphase and telophase, we suggest that its activity is downregulated.

Documentos Relacionados

• Characterization of microtubule binding domains in the Arabidopsis kinesin-like calmodulin binding protein.
• Origin and Evolution of Kinesin-Like Calmodulin-Binding Protein1[w]
• The Cotton Kinesin-Like Calmodulin-Binding Protein Associates with Cortical Microtubules in Cotton Fibers1
• The Ras-like GTPase Gem is involved in cell shape remodelling and interacts with the novel kinesin-like protein KIF9
• Kinesin-like protein CENP-E is upregulated in rheumatoid synovial fibroblasts