Internally-nucleated fibres were a persistent feature of skeletal muscle from <i>Tg(ACTA1)^D286G-EGFP</i> mice post-weaning.

<p>(A) Representative images taken of Hoechst-labeled EDL and SOL muscles from PN d14, 1 and 4-month old <i>Tg(ACTA1)^D286G-EGFP</i> mice showed the occurrence of internally-nucleated fibres in post-weaned <i>Tg(ACTA1)^D286G-EGFP</i> mice. A representative image of a WT EDL muscle labelled with phalloidin-FITC and Hoechst is also shown. (B) The percentage of internally-nucleated fibres in whole EDL (1m, 4m WT: <i>n = 7</i>, <i>n = 6</i>; <i>Tg</i>: <i>n = 10</i>, <i>n = 5</i>) and SOL (1m, 4m WT: <i>n = 9</i>, <i>n = 5</i>; <i>Tg</i>: <i>n = 8</i>, <i>n = 5</i>) muscles was determined for WT and <i>Tg(ACTA1)^D286G-EGFP</i> mice, with a significant increase seen in <i>Tg(ACTA1)^D286G-EGFP</i> muscle. However there was no significant difference in the number of internally nucleated fibres in EDL and SOL muscles (WT: <i>n = 7</i>, <i>Tg</i>: <i>n = 4</i>) of <i>Tg(ACTA1)^D286G-EGFP</i> mice at PN d14. *<i>p<0.05</i> compared to WT, **<i>p<0.01</i> compared to WT.