Advanced Review
7SK snRNA: a noncoding RNA that plays a major role in regulating eukaryotic transcription
B. Matija Peterlin,
John E. Brogie,
David H. Price,
Corresponding Author
B. Matija Peterlin
Department of Medicine, Rosalind Russel Medical Research Center, University of California, San Francisco, CA, USA
Department of Microbiology, Rosalind Russel Medical Research Center, University of California, San Francisco, CA, USA
Department of Immunology, Rosalind Russel Medical Research Center, University of California, San Francisco, CA, USA
Department of Virology, Haartman Institute, University of Helsinki, Helsinki, Finland
Department of Medicine, Rosalind Russel Medical Research Center, University of California, San Francisco, CA, USASearch for more papers by this authorJohn E. Brogie
Biochemistry Department, University of Iowa, Iowa City, IA, USA
Search for more papers by this authorDavid H. Price
Biochemistry Department, University of Iowa, Iowa City, IA, USA
Search for more papers by this author
B. Matija Peterlin,
John E. Brogie,
David H. Price,
Corresponding Author
B. Matija Peterlin
Department of Medicine, Rosalind Russel Medical Research Center, University of California, San Francisco, CA, USA
Department of Microbiology, Rosalind Russel Medical Research Center, University of California, San Francisco, CA, USA
Department of Immunology, Rosalind Russel Medical Research Center, University of California, San Francisco, CA, USA
Department of Virology, Haartman Institute, University of Helsinki, Helsinki, Finland
Department of Medicine, Rosalind Russel Medical Research Center, University of California, San Francisco, CA, USASearch for more papers by this authorJohn E. Brogie
Biochemistry Department, University of Iowa, Iowa City, IA, USA
Search for more papers by this authorDavid H. Price
Biochemistry Department, University of Iowa, Iowa City, IA, USA
Search for more papers by this authorAbstract
The human 7SK small nuclear RNA (snRNA) is an abundant noncoding RNA whose function has been conserved in evolution from invertebrates to humans. It is transcribed by RNA polymerase III (RNAPIII) and is located in the nucleus. Together with associated cellular proteins, 7SK snRNA regulates the activity of the positive transcription elongation factor b (P-TEFb). In humans, this regulation is accomplished by the recruitment of P-TEFb by the 7SK snRNA-binding proteins, hexamethylene bisacetamide (HMBA)-induced mRNA 1/2 (HEXIM1 or HEXIM2), which inhibit the kinase activity of P-TEFb. P-TEFb regulates the transition of promoter proximally paused RNA polymerase II (RNAPII) into productive elongation, thereby, allowing efficient mRNA production. The protein composition of the 7SK small nuclear ribonucleoprotein (snRNP) is regulated dynamically. While the Lupus antigen (La)-related protein 7 (LARP7) is a constitutive component, the methylphosphate capping enzyme (MePCE) associates secondarily to phosphorylate the 5′ end of 7SK snRNA. The release of active P-TEFb is closely followed by release of HEXIM proteins and both are replaced by heterogeneous nuclear ribonucleoproteins (hnRNPs). The released P-TEFb activates the expression of most cellular and viral genes. Regulated release of P-TEFb determines the expression pattern of many of the genes that respond to environmental stimuli and regulate growth, proliferation, and differentiation of cells. WIREs RNA 2012, 3:92–103. doi: 10.1002/wrna.106
This article is categorized under:
- RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems
- RNA Interactions with Proteins and Other Molecules > Protein–RNA Recognition
- RNA Processing > Processing of Small RNAs
- Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs
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