The functions of the vast majority of non-coding RNA transcripts remain elusive. Most act as RNA guides for protein enzymes. Several non-coding RNAs (ncRNAs) regulate eukaryotic mRNA transcription. ncRNAs typically function as ribonucleoprotein (RNP) complexes and not as naked RNAs.
Non-coding RNAs (ncRNAs) with gene regulatory functions are starting to be seen as a common feature of mammalian gene regulation with the discovery that most of the transcriptome is ncRNA. The prototype has long been the Xist ncRNA, which induces X-chromosome inactivation in female cells.
Xist-like model is only one of many possible solutions and that imprinted ncRNAs could provide the better model for understanding the function of the new class of ncRNAs associated with non-imprinted mammalian genes. It creates a new paradigm: the silencing of imprinted gene clusters by long ncRNAs.
Embryogenesis
Non-coding RNAs (ncRNAs) are emerging as key regulators of embryogenesis. They control embryonic gene expression by several means, ranging from microRNA-induced degradation of mRNAs to long ncRNA-mediated modification of chromatin.
Many aspects of embryogenesis seem to be controlled by ncRNAs, including the maternal-zygotic transition, the maintenance of pluripotency, the patterning of the body axes, the specification and differentiation of cell types and the morphogenesis of organs.
There are two emerging themes for ncRNA function: promoting developmental transitions and maintaining developmental states. These examples highlight the roles of ncRNAs in ensuring a robust commitment to one of two possible cell fates.
See also
RNA-guided proteins
ncRNA transcriptional regulators
small RNAs
- small nuclear RNAs
- small nucleolar RNAs
References
Non-coding RNAs as regulators of embryogenesis. Pauli A, Rinn JL, Schier AF. Nat Rev Genet. 2011 Feb;12(2):136-49. PMID: 21245830
Matera AG, Terns RM, Terns MP. Non-coding RNAs: lessons from the small nuclear and small nucleolar RNAs. Nat Rev Mol Cell Biol. 2007 Mar;8(3):209-20. PMID: 17318225
Goodrich JA, Kugel JF. Non-coding-RNA regulators of RNA polymerase II transcription. Nat Rev Mol Cell Biol. 2006 Aug;7(8):612-6. Epub 2006 May 24. PMID: 16723972
Huttenhofer A, Schattner P. The principles of guiding by RNA: chimeric RNA-protein enzymes. Nat Rev Genet. 2006 Jun;7(6):475-82. PMID: 16622413
