This Title All WIREs
How to cite this WIREs title:
WIREs Dev Biol
Impact Factor: 5.814

Stem cells in skeletal muscle growth and regeneration in amniotes and teleosts: Emerging themes

Full article on Wiley Online Library:   HTML PDF

Can't access this content? Tell your librarian.

Abstract Skeletal muscle is a contractile, postmitotic tissue that retains the capacity to grow and regenerate throughout life in amniotes and teleost. Both muscle growth and regeneration are regulated by obligate tissue resident muscle stem cells. Given that considerable knowledge exists on the myogenic process, recent studies have focused on examining the molecular markers of muscle stem cells, and on the intrinsic and extrinsic signals regulating their function. From this, two themes emerge: firstly, muscle stem cells display remarkable heterogeneity not only with regards to their gene expression profile, but also with respect to their behavior and function; and secondly, the stem cell niche is a critical regulator of muscle stem cell function during growth and regeneration. Here, we will address the current understanding of these emerging themes with emphasis on the distinct processes used by amniotes and teleost, and discuss the challenges and opportunities in the muscle growth and regeneration fields. This article is characterized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches Early Embryonic Development > Development to the Basic Body Plan Vertebrate Organogenesis > Musculoskeletal and Vascular
Temporal sequence of myogenic regulatory factor expression during muscle regeneration. Following skeletal muscle damage, quiescent satellite cells (PAX7) become activated, proliferate, differentiate and fuse to form nascent myofibers to affect repair. This myogenic program is governed by the four myogenic regulatory factors (MRFs), which act as master regulators of myogenesis. A myogenic lineage is determined by myogenic factor 5 (MYF5), which in turn induces myoblast determination protein (MYOD) that drives cells down a myogenic lineage. Later on in the program myogenin (MYOG) expression is critical for terminal differentiation. Muscle specific regulatory factor 4 (MRF4) too contributes to terminal differentiation
[ Normal View | Magnified View ]
Cross talk between satellite cells and components of the regenerative milieu. Under homeostatic conditions satellite cells reside in a specialized niche between the muscle sarcolemma and the basal lamina. Injury disrupts the environment the quiescent satellite cells experience leading it to become active, differentiate and fuse to repair damaged fibers and generate nascent myofibers. The temporarily established repair niche is composed of a multitude of cells that promote a coordinated response secreting cytokines that selectively regulate discrete stages of the satellite cell driven myogenic program to ensure successful muscle repair. FAPs, fibro‐adipogenic progenitors; PICs, PW1+/PAX7 interstitial cells; Tregs, regulatory T cells
[ Normal View | Magnified View ]
Muscle growth strategies utilized by amniotes and teleosts. (a) While early postnatal muscle growth in amniotes occurs via satellite cell nuclear accretion, stem cell independent hypertrophy is used during the later stages. (b) Teleost on the other hand, use all three strategies: stratified hyperplasia, mosaic hyperplasia and hypertrophy
[ Normal View | Magnified View ]

Browse by Topic

Vertebrate Organogenesis > Musculoskeletal and Vascular
Early Embryonic Development > Development to the Basic Body Plan
Adult Stem Cells, Tissue Renewal, and Regeneration > Tissue Stem Cells and Niches