Figure 4
TFAM knockdown leads to reduced detachment of mt-nucleoids. (a) Effect of TFAM knockdown on mt-nucleoids. Knockdown of TFAM was performed in HeLa cells. mtDNAs were stained with SYBR Green I in TFAM-knockdown cells. Time after transfection of siRNAs is shown in the upper left of the images. Note that mt-nucleoid enlargement is observed from 10 h after transfection. Arrowheads indicate enlarged mt-nucleoids. Scale bar, 10 μm. (b) Proportion of mt-nucleoids undergoing attachment and detachment in wild-type and TFAM-knockdown HeLa cells. The significance of differences was examined by Student’s t-test (p = 0.0947). N.S., not significant. A total of 20 to 48 mt-nucleoids per cell were randomly selected and analyzed. Error bars indicate standard deviation (ncells = 6 for each condition). (c) Frequency of attachment and detachment per mt-nucleoid in wild-type and TFAM-knockdown HeLa cells in 2 min. The frequency was analyzed in mt-nucleoids undergoing attachment and detachment. A total of 20 to 48 mt-nucleoids per cell were randomly selected and analyzed. Error bars indicate standard deviation (ncells = 6 for each condition). The significance of differences in attachment and detachment was examined by paired t-test (WT, p = 0.1281; TFAM RNAi, p = 0.0007). N.S., not significant.
