Fig. 4

Upregulation of miR-101a between 7 and 14dpa is essential for scar tissue removal. (A-I) Control and Tg(hs:miR-101a-sp) animals were subjected to ventricular resection and heat treated at defined intervals. Hearts were collected at 30dpa and processed for AFOG staining to identify scar tissue. (A-C) Heat-treated induced depletion of miR-101a from 0 to 7dpa did not alter scar tissue removal between control and Tg(hs:miR-101a-sp) hearts. (D-F) Suppression of miR-101a expression between 7 and 30dpa resulted in increased scarring in Tg(hs:miR-101a-sp) hearts, compared with controls. (G-I) miR-101a suppression from 14 to 30dpa, however, led to normal scar tissue clearance in control and Tg(hs:miR-101a-sp) hearts. Dashed lines indicate approximate resection injury plane. (J) Quantification of scarring indices demonstrates that increased miR-101a expression at 7-14dpa is required for scar tissue clearance. ct, control. n=4-8; *P<0.01 (Student′s t-test); NS, not significant; error bars represent s.e.m.