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Program in Molecular Medicine

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Animals; Animals, Genetically Modified; Drosophila; Female; Gene Expression Regulation, Developmental; Larva; Life Cycle Stages; Male; Metamorphosis, Biological; MicroRNAs; Muscles; Nervous System; Neuromuscular Junction; Transgenes


Biochemistry | Developmental Biology | Molecular Biology | Molecular Genetics


The Drosophila let-7-Complex (let-7-C) is a polycistronic locus encoding three ancient microRNAs: let-7, miR-100, and fly lin-4 (miR-125). We find that the let-7-C locus is principally expressed in the pupal and adult neuromusculature. let-7-C knockout flies appear normal externally but display defects in adult behaviors (e.g., flight, motility, and fertility) as well as clear juvenile features in their neuromusculature. We find that the function of let-7-C to ensure the appropriate remodeling of the abdominal neuromusculature during the larval-to-adult transition is carried out predominantly by let-7 alone. This heterochronic role of let-7 is likely just one of the ways in which let-7-C promotes adult behavior.


let-7, let-7-Complex, microRNA, heterochronic developmental timing, neuromuscular junction

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Genes Dev. 2008 Jun 15;22(12):1591-6. doi: 10.1101/gad.1671708. Link to article on publisher's site

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Genes and development

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Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License