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Conditional gene expression and RNAi using MEC-8-dependent splicing in C. elegans.

ABSTRACT: We describe a method for conditional regulation of gene expression based on the processing of an intron cassette. The RNA processing factor MEC-8 is necessary for the function of the Caenorhabditis elegans touch receptor neurons; mec-8 mutants are touch insensitive. We show here that this insensitivity involves the loss of MEC-8-dependent splicing of mec-2, which encodes a component of the mechanosensory transduction complex. MEC-8 is needed to remove the ninth intron in mec-2 pre-mRNA to form the longest of three mRNAs, mec-2a. Without MEC-8, splicing causes the termination of the transcript. Inclusion of mec-2 intron 9 is sufficient to convey mec-8-dependent regulation on other genes and, in mec-8(u218ts) mutants, resulted in their temperature-dependent expression. Because mec-8 is expressed ubiquitously in embryos and extensively in larvae, this system should produce temperature-sensitive expression for most genes. As an example, we report a strain that exhibits temperature-dependent RNA interference.

SUBMITTER: Calixto A

PROVIDER: S-EPMC2862115 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

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Conditional gene expression and RNAi using MEC-8-dependent splicing in C. elegans.

Calixto Andrea A Ma Charles C Chalfie Martin M

Nature methods 20100404 5

We describe a method for conditional regulation of gene expression based on the processing of an intron cassette. The RNA processing factor MEC-8 is necessary for the function of the Caenorhabditis elegans touch receptor neurons; mec-8 mutants are touch insensitive. We show here that this insensitivity involves the loss of MEC-8-dependent splicing of mec-2, which encodes a component of the mechanosensory transduction complex. MEC-8 is needed to remove the ninth intron in mec-2 pre-mRNA to form t ...[more]

PMID: 20364149

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