Figure 2: SDS-PAGE analysis of titin and nebulin expression in striated muscles of control and flight mice. (a) m. psoas; (b) m. tibialis anterior; (c), m. gastrocnemius; (d) cardiac muscle. T2 is proteolytic fragment of titin (m.w. ~2000–2100 kDa). N2B, N2BA, N2A, and NT are isoforms of intact titin (T1, m.w. ~3000–3700 kDa). NT-isoforms of titin were recently found in striated muscles of mammals [31]. The content of NT-titin in mouse striated muscles is ~10%.