摘要
Type I male midshipman fish produce high-frequency hums for prolonged durations using sonic muscle fibers, each of which contains a hollow tube of radially oriented thin and flat myofibrils that display extraordinarily wide (∼1.2μm) Z bands. We have revealed an elaborate cytoskeletal network of desmin filaments associated with the contractile cylinder that form interconnected concentric ring structures in the core and periphery at the level of the Z bands. Stretch and release of single fibers revealed reversible length changes in the elastic desmin lattice. This lattice is linked to Z bands via novel intracellular desmosome-like junctional complexes that collectively form a ring, termed the "Z corset," around the periphery and within the core of the cylinder. The junctional complex consists of regularly spaced parallel ∼900-nm-long cytoskeletal rods, or "Z bars," interconnected with slender (3-4nm) plectin-positive filaments. Z bars are linked to the Z band by plectin filaments and on the opposite side to a dense mesh of desmin filaments. Adjacent Z bands are linked by slender filaments that appear to suspend sarcotubules. We propose that the highly reinforced elastic desmin cytoskeleton and the unique Z band junctions are structural adaptations that enable the muscles' high-frequency and high-endurance activity.
原文 | 英語 |
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頁(從 - 到) | 56-71 |
頁數 | 16 |
期刊 | Journal of Structural Biology |
卷 | 143 |
發行號 | 1 |
DOIs | |
出版狀態 | 已發佈 - 7月 1 2003 |
對外發佈 | 是 |
ASJC Scopus subject areas
- 結構生物學