Trunk exoskeleton in teleosts is mesodermal in origin
نویسندگان
چکیده
The vertebrate mineralized skeleton is known to have first emerged as an exoskeleton that extensively covered the fossil jawless fish. The evolutionary origin of this exoskeleton has long been attributed to the emergence of the neural crest, but experimental evaluation for this is still poor. Here we determine the embryonic origin of scales and fin rays of medaka (teleost trunk exoskeletons) by applying long-term cell labelling methods, and demonstrate that both tissues are mesodermal in origin. Neural crest cells, however, fail to contribute to these tissues. This result suggests that the trunk neural crest has no skeletogenic capability in fish, instead highlighting the dominant role of the mesoderm in the evolution of the trunk skeleton. This further implies that the role of the neural crest in skeletogenesis has been predominant in the cephalic region from the early stage of vertebrate evolution.
منابع مشابه
Mesodermal origin of median fin mesenchyme and tail muscle in amphibian larvae
Mesenchyme is an embryonic precursor tissue that generates a range of structures in vertebrates including cartilage, bone, muscle, kidney, and the erythropoietic system. Mesenchyme originates from both mesoderm and the neural crest, an ectodermal cell population, via an epithelial to mesenchymal transition (EMT). Because ectodermal and mesodermal mesenchyme can form in close proximity and give ...
متن کاملارزشیابی وضعیت انجام کار به روش RULA در یکی از صنایع خودرو- نیروی محرکه با هدف طراحی موثر سیستم کمک حرکتی اگزواسکلتال
Background and aims : physical activities in occupations like handling, static and dynamic postures, sudden movements, and repetitive postures are amongst most important risk factors of Work related Musculoskeletal Disorders (WMSDs). There are many ergonomic methods for assessing WMSDs which can be used in different cases, but these assessments and analyses can not be beneficial by themselves...
متن کاملMicroglia as a stem cell
Microglia is considered the only cell population of mesodermal origin, which comprises 10% of the cells in brain parenchyma. Recent neural stem cell (NSC) studies demonstrate that the brain has regenerative potential. NSCs do not give rise to microglial cells, however indicating that NSCs alone cannot complete the regenetion of the brain. Although the role of microglia is not fully understood, ...
متن کاملAllometric growth of the trunk leads to the rostral shift of the pelvic fin in teleost fishes.
The pelvic fin position among teleost fishes has shifted rostrally during evolution, resulting in diversification of both behavior and habitat. We explored the developmental basis for the rostral shift in pelvic fin position in teleost fishes using zebrafish (abdominal pelvic fins) and Nile tilapia (thoracic pelvic fins). Cell fate mapping experiments revealed that changes in the distribution o...
متن کاملEffect of Target Impedance Selection on the Lower Extremity Assistive Exoskeleton Performance
Exoskeletons are utilized extensively in robotic rehabilitation and power augmentation purposes. One of the most recognised control algorithms utilized in this field is the impedance controller. Impedance control approach provides the capability of realizing different rehabilitation exercises by tuning the target impedance gains. Trial and error experimental approach is one of the most common m...
متن کامل