Small non-coding RNAs in animal development

The functional roles of small non-coding RNAs in vertebrates are beginning to be elucidated thanks to specific gene-deletion approaches.miR-15, miR-16 and miR-430 are involved in modulation of the Nodal signalling pathway in different phases of vertebrate embryonic development.miR-124 contributes to the adoption of neural cell fate by regulating the switch between PTB and nPTB, two regulators of alternative splicing.miR-208 deletion results in a failure to produce cardiac hypertrophy in response to various stresses.miR-181 and miR-155 have a complex regulatory role in lymphocyte maturation and the immune response.piRNAs are a novel class of small non-coding RNAs that are expressed in the germline, and that are possibly involved in inhibiting the mobilization of transposons.