Fig. 1.

Auf1^−/− satellite cells show aberrant terminal differentiation. (A) Representative cultured mass preparation of hindlimb skeletal muscles harvested from 4-mo-old mice, 10 d in culture. n = 3. Proliferating myoblasts (MyoD), white arrows; elongated myocytes (Myogenin), orange arrows; myofibers, yellow arrows. Nuclei stained with DAPI. (B) Representative IF staining of MyoD (green) and Myogenin (red) in WT and AUF1 KO-isolated myofibers, cultured for 72 h. Ten myofibers analyzed per mouse, n = 3. (C) Representative IF staining of Flag-AUF1 (red) and nuclei (DAPI, blue) in WT and AUF1 KO myofibers. Myofibers from mass preparations of the TA muscle as in A transduced with lentivirus vectors expressing AUF1 cDNAs for 72 h. Ten myofibers per group analyzed, n = 3. (D) Quantification of nuclei number and AUF1 in myofibers transduced with individual AUF1 isoforms, as in C, n = 3. (Scale bars: 100 μm.)