lmmunolocaization of Actin in Transgenic and Wildtype Murine Myocardium
Location
CSU Ballroom
Start Date
21-4-2008 1:00 PM
End Date
21-4-2008 3:00 PM
Student's Major
Biological Sciences
Student's College
Science, Engineering and Technology
Mentor's Name
Marilyn C. Hart
Mentor's Department
Biological Sciences
Mentor's College
Science, Engineering and Technology
Description
In myocardium, actin and myosin filaments are organized into repeating units of sarcomeres, the basic unit of muscle contraction. Actin Capping Protein (CP) binds to the barbed ends of the actin filament at the Zline, directing and maintaining the proper organization of the thin filament in the sarcomere. CP is a heterodimer composed of an alpha (a) and a beta (P) subunit. Muscle cells contain two p subunit isoforms, β1 and β2. The β1 isoform is present at the Z line; the β2 isoform is found elsewhere including cell-cell junctions. In previous studies, transgenic mice were generated that replaced the β1 isoform with the β2 isoform. We hypothesized that a decrease in βl expression will lead to a disorganized myofibrillar structure and that the disorganization will become increasingly severe as a function of murine age. We examined the myocardium of transgenic mice ranging in age from three months to twelve months. Murine hearts were extracted and frozen sections prepared using a cryomicrotome. The tissue sections were fixed, quenched with ethanolamine, permeabilized with methanol, and washed in phosphate buffered saline. The sections were probed with mouse anti-actin-Cy3 rhodamine conjugated antibody and images captured using an Olympus fluorescent microscope and Simple PCI 6 acquisition software with deconvolution. Three month myocardium exhibited minor disorganization of the Z-lines compared to six, nine, and twelve month myocardium. The Z-lines in the twelve month myocardium were grossly disorganized with irregular breaks. In addition, the spacing between Z-lines was variable indicative of altered actin filament length.
lmmunolocaization of Actin in Transgenic and Wildtype Murine Myocardium
CSU Ballroom
In myocardium, actin and myosin filaments are organized into repeating units of sarcomeres, the basic unit of muscle contraction. Actin Capping Protein (CP) binds to the barbed ends of the actin filament at the Zline, directing and maintaining the proper organization of the thin filament in the sarcomere. CP is a heterodimer composed of an alpha (a) and a beta (P) subunit. Muscle cells contain two p subunit isoforms, β1 and β2. The β1 isoform is present at the Z line; the β2 isoform is found elsewhere including cell-cell junctions. In previous studies, transgenic mice were generated that replaced the β1 isoform with the β2 isoform. We hypothesized that a decrease in βl expression will lead to a disorganized myofibrillar structure and that the disorganization will become increasingly severe as a function of murine age. We examined the myocardium of transgenic mice ranging in age from three months to twelve months. Murine hearts were extracted and frozen sections prepared using a cryomicrotome. The tissue sections were fixed, quenched with ethanolamine, permeabilized with methanol, and washed in phosphate buffered saline. The sections were probed with mouse anti-actin-Cy3 rhodamine conjugated antibody and images captured using an Olympus fluorescent microscope and Simple PCI 6 acquisition software with deconvolution. Three month myocardium exhibited minor disorganization of the Z-lines compared to six, nine, and twelve month myocardium. The Z-lines in the twelve month myocardium were grossly disorganized with irregular breaks. In addition, the spacing between Z-lines was variable indicative of altered actin filament length.
Recommended Citation
Bohland, Meghan. "lmmunolocaization of Actin in Transgenic and Wildtype Murine Myocardium." Undergraduate Research Symposium, Mankato, MN, April 21, 2008.
https://cornerstone.lib.mnsu.edu/urs/2008/poster-session-B/2
