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Transgenic microRNA inhibition with spatiotemporal specificity in intact organisms.

ABSTRACT: MicroRNAs are important regulators of gene expression, yet the functional outputs of most microRNA-target interactions remain elusive. Here we introduce the Drosophila melanogaster microRNA sponge (miR-SP) as a powerful transgenic technology to dissect the function of every microRNA with precise spatiotemporal resolution. miR-SPs can be used to characterize tissue-specific microRNA loss-of-function phenotypes, define the spatial regulation of their effectors and uncover interactions between microRNAs and other genes. Using themiR-SP system, we identified an essential role of the conserved microRNA miR-8, in neuromuscular junction formation. Tissue-specific silencing revealed that postsynaptic activity of miR-8 is important for normal neuromuscular junction morphogenesis. Given that miR-SPs rely on a bipartite modular expression system, they could be used to elucidate the endogenous function of microRNAs in any species in which conditional expression can be achieved.

SUBMITTER: Loya CM

PROVIDER: S-EPMC3183579 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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Transgenic microRNA inhibition with spatiotemporal specificity in intact organisms.

Loya Carlos M CM Lu Cecilia S CS Van Vactor David D Fulga Tudor A TA

Nature methods 20091115 12

MicroRNAs are important regulators of gene expression, yet the functional outputs of most microRNA-target interactions remain elusive. Here we introduce the Drosophila melanogaster microRNA sponge (miR-SP) as a powerful transgenic technology to dissect the function of every microRNA with precise spatiotemporal resolution. miR-SPs can be used to characterize tissue-specific microRNA loss-of-function phenotypes, define the spatial regulation of their effectors and uncover interactions between micr ...[more]

PMID: 19915559

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