Fig. 1
From: MMP-2 is a novel histone H3 N-terminal protease necessary for myogenic gene activation
Accumulation of a chromatin-bound H3cl product during skeletal myogenesis. a Light microscopy (10x) of LADD stained mouse C2C12 and rat L6 myoblasts (day 0) cultured in differentiation media that induces cell fusion, multinucleation and formation of striated myotubes (day 4). The L6.G8 myoblasts, a derivative of L6, do not form myotubes. b A histone H3 C-terminal antibody was used for Western analysis of chromatin purified from myoblasts and human HEK293 kidney cells c cultured in differentiation media for the indicated number of days. Proteolysis of the H3 N-terminus (H3NT) generates a fast-migrating cleaved H3 (H3cl) product as indicated. Amido black staining (AB) of membranes was performed to confirm equivalent loading of chromatin between samples. d Western analysis of chromatin isolated from C2C12 myoblasts (D0) and myotubes (D4) using antibodies to detect proteolysis of core histones H3, H2B, H2A or H4. e Western analysis of chromatin of C2C12 myotubes (MT) enriched from the remaining undifferentiated reserve cells (RC) after 4 days in differentiation media. f Representative Western analysis of chromatin extracted from adult mouse skeletal muscle (SM) tissue compared to C2C12 myotube (MT) chromatin. The protein ladder indicates the relative size of histones H3 (15 kDa) and H4 (10 kDa)