alpha-Actinin Is Required for the Proper Assembly of Z-Disk/Focal-Adhesion-Like Structures and for Efficient Locomotion in Caenorhabditis elegans

作者：Moulder Gary L; Cremona Gina H; Duerr Janet; Stirman Jeffrey N; Fields Stephen D; Martin Wendy; Qadota Hiroshi; Benian Guy M; Lu Hang; Barstead Robert J^*

来源：Journal of Molecular Biology, 2010, 403(4): 516-528.

DOI：10.1016/j.jmb.2010.08.055

• alpha-actinin
• focal adhesion
• muscle
• Caenorhabditis elegans

The actin binding protein a-actinin is a major component of focal adhesions found in vertebrate cells and of focal-adhesion-like structures found in the body wall muscle of the nematode Caenorhabditis elegans. To study its in vivo function in this genetic model system, we isolated a strain carrying a deletion of the single C. elegans alpha-actinin gene. We assessed the cytological organization of other C. elegans focal adhesion proteins and the ultrastructure of the mutant. The mutant does not have normal dense bodies, as observed by electron microscopy; however, these dense-body-like structures still contain the focal adhesion proteins integrin, talin, and vinculin, as observed by immunofluorescence microscopy. Actin is found in normal-appearing I-bands, but with abnormal accumulations near muscle cell membranes. Although swimming in water appeared grossly normal, use of automated methods for tracking the locomotion of individual worms revealed a defect in bending. We propose that the reduced motility of alpha-actinin null is due to abnormal dense bodies that are less able to transmit the forces generated by actin/myosin interactions.

• 出版日期2010-11-5