Dynamic Changes in Sarcoplasmic Reticulum Structure in Ventricular Myocytes
Figure 8
The microtubule-associated motors dynein and Kif5b regulate SR motility in ventricular myocytes. (a) Confocal image of neonatal ventricular myocyte expressing tRFP-SR under control conditions and after 120 minutes of 30 μM EHNA perfusion. Corbular SR boutons are identified with colored circles. (b) Confocal images of neonatal ventricular myocyte expressing tRFP-SR (left) and Kif5b-WT-BFP (top/center) or Kif5b-DN-BFP (bottom/center). The images to the right were generated by merging the tRFP-SR and Kif5b-BFP images. (c) Bar plot of the mean total distance traveled by corbular SR boutons before and after EHNA perfusion and myocytes infected with tRFP-SR (control) and myocytes infected with tRFP-SR and Kif5B-DN-BFP. (d) Confocal images showing tRFP-SR fluorescence of adult ventricular myocytes under control conditions (top) and incubated in the presence of 30 μM EHNA (bottom). Surface plots show the time-course of fluorescence intensity in the region delineated by the white box. (e) Cartoon depicting a hypothetical model for the regulation of SR structure and motility in ventricular myocytes (LTCC = L-type Ca2+ channel; RyR = ryanodine receptor).
