Xenopus laevis, the African clawed frog, undergoes seasonal estivation to survive periods of drought when its lake-bed habitats dry up. The frog can lose ∼30 % of its total body… Click to show full abstract
Xenopus laevis, the African clawed frog, undergoes seasonal estivation to survive periods of drought when its lake-bed habitats dry up. The frog can lose ∼30 % of its total body water, leading to conditions of impaired blood flow and ischemia which risk cellular survival under these harsh conditions. MicroRNAs are short, noncoding, single-stranded RNAs 21-24 nt long that have been widely implicated in hypometabolic responses, and serve functions including apoptosis survival. The levels of three pro-apoptotic and four anti-apoptotic miRNAs were measured in liver and skeletal muscle of estivating X. laevis, and bioinformatic analysis was performed to verify potential mRNA targets of these miRNAs. Members of pro-apoptotic miRNAs miR-15a, miR-16, and miR-101 showed upregulation as a result of dehydration stress, while anti-apoptotic miRNAs miR-19b, miR-21, miR-92a, and miR-155 showed differential regulation between the two tissues. Together, these miRNAs act in a more diverse fashion than arbitrarily pro- or anti-apoptotic, and encompass functions ranging from the inhibition of cell proliferation through cell cycle arrest to the prevention of skeletal muscle atrophy.
               
Click one of the above tabs to view related content.