Dense bands and polarity of thin filament at myotendinous junction in guppy muscle

摘要: Guppy muscle shows unique electron dense bands in the terminal segment of myofibril at muscle—tendon junction. On occasion were also observed myomyous The unusual are approximately 70 nm wide with an density similar to that Z-lines. Thin filaments seem be continuous throughout these no interdigitation before membrane. Calcium-activated neutral protease removes bands. decorated by heavy meromyosin and therefore actin. polarity actin filaments, determined arrowhead pattern formed when HMM, appears directed away from sarcolemma. No evidence reversal was Although function significance is unknown, we assume guppy not Z-lines, but rather, structures muscle.