Plasticity of lung development in the amphibian, Xenopus laevis
نویسندگان
چکیده
Contrary to previous studies, we found that Xenopus laevis tadpoles raised in normoxic water without access to air can routinely complete metamorphosis with lungs that are either severely stunted and uninflated or absent altogether. This is the first demonstration that lung development in a tetrapod can be inhibited by environmental factors and that a tetrapod that relies significantly on lung respiration under unstressed conditions can be raised to forego this function without adverse effects. This study compared lung development in untreated, air-deprived (AD) and air-restored (AR) tadpoles and frogs using whole mounts, histology, BrdU labeling of cell division and antibody staining of smooth muscle actin. We also examined the relationship of swimming and breathing behaviors to lung recovery in AR animals. Inhibition and recovery of lung development occurred at the stage of lung inflation. Lung recovery in AR tadpoles occurred at a predictable and rapid rate and correlated with changes in swimming and breathing behavior. It thus presents a new experimental model for investigating the role of mechanical forces in lung development. Lung recovery in AR frogs was unpredictable and did not correlate with behavioral changes. Its low frequency of occurrence could be attributed to developmental, physical and behavioral changes, the effects of which increase with size and age. Plasticity of lung inflation at tadpole stages and loss of plasticity at postmetamorphic stages offer new insights into the role of developmental plasticity in amphibian lung loss and life history evolution.
منابع مشابه
Expression of hsp90 Alpha and hsp90 Beta during Xenopus laevis Embryonic Development
Background: Members of the eukaryotic Hsp90 family function as important molecular chaperones in the assembly, folding and activation of cellular signaling in development. Two hsp90 genes, hsp90 alpha and hsp90 beta, have been identified in fish and homeothermic vertebrates but not in poikilothermic vertebrates. In the present study, the expression of hsp90 alpha and hsp90 beta genes in Xenopus...
متن کاملThe S362A mutation block ROMK2 (Kir1.1b) endocytosis in Xenopus laevis oocyte membrane .
Abstract The S362A mutation block ROMK2 (Kir1.1b) endocytosis in Xenopus laevis oocyte membrane . Saeed Hajihashemi1 , 1-Assistant professor, PhD in Physiology, Department of Physiology, School of Medical science, Arak University of Medical Sciences. Introduction: ROMK channel is localized on the apical membrane of the nephron. Recent studies suggest that endocytosis of ROMK chan...
متن کاملIntegrin Linked Kinase (X-ILK) Function during Embryonic Development and within Adult Tissues of Xenopus laevis
Integrin linked kinase (ILK) is a serine/threonine protein kinase implicated in the phosphatidylinositol 3’kinase (PI3’K) pathway. Integrin linked kinase has been investigated in different organisms such as mammalian systems (human, mice, rat), insects (Drosophila) and nematodes (Cenorhabditis elegans), however to date little data regarding ILK research on amphibians has been reported. In...
متن کاملCorticosterone promotes emergence of fictive air breathing in Xenopus laevis Daudin tadpole brainstems.
The emergence of air breathing during amphibian metamorphosis requires significant changes to the brainstem circuits that generate and regulate breathing. However, the mechanisms controlling this developmental process are unknown. Because corticosterone plays an important role in the neuroendocrine regulation of amphibian metamorphosis, we tested the hypothesis that corticosterone augments fict...
متن کامل