Purification of an actin-binding protein composed of 115-kDa polypeptide from pollen tubes of lily.
From lily pollen tubes, an actin-binding protein composed of 115-kDa polypeptide was purified sequentially by co-precipitation method with F-actin, hydroxylapatite column, gel filtration column and DE-52 ion exchange column chromatography. This component displayed a tendency to aggregate in solutions of low ionic strength, indicating a hydrophilic characteristic. Under physiological ionic conditions, this component bound to F-actin in an actin-concentration-dependent was saturable manner. Binding of this component to F-actin was independent of ATP and Ca(2+)-concentrations. Fluorescent microscopy revealed that F-actin labeled with rhodamine-phalloidin showed bundling in the presence of this component. Judging from the lack of antibody cross-reactivity, this component does not seem to be related to alpha-actinin of skeletal muscle and plant 135-kDa actin-bundling protein. Therefore, this component is the F-actin binding protein, which has not been identified thus far in plant cells.
Department of Life Science, Faculty of Science, Himeji Institute of Technology, Hyogo, Japan.
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T
Nakayasu
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E
Yokota
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Shimmen
D000199:Actins / Q000378:metabolism; D019668:Liliaceae / Q000378:metabolism*; D008840:Microfilament Proteins / Q000302:isolation & purification* / Q000378:metabolism*; D010940:Plant Proteins / Q000302:isolation & purification* / Q000378:metabolism*
D000199:Actins; D008840:Microfilament Proteins; D010940:Plant Proteins