Increased association of 7SK snRNA with Tat cofactor P-TEFb following activation of peripheral blood lymphocytes
| Autor: | Richard E. Haaland, Andrew P. Rice, Christine H. Herrmann |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
Cyclin T1
Transcription Genetic T-Lymphocytes genetic processes Immunology information science Biology Lymphocyte Activation environment and public health Transcription (biology) Cyclins RNA Small Nuclear 7SK RNA Gene expression Humans Immunology and Allergy Positive Transcriptional Elongation Factor B P-TEFb urogenital system Kinase Cyclin T RNA Blotting Northern Cyclin-Dependent Kinase 9 Precipitin Tests Molecular biology Infectious Diseases Solubility health occupations Small nuclear RNA HeLa Cells |
| Zdroj: | AIDS. 17:2429-2436 |
| ISSN: | 0269-9370 |
| DOI: | 10.1097/00002030-200311210-00004 |
| Popis: | Objective This study was undertaken to determine whether 7SK small nuclear RNA (snRNA), which has been proposed to function as an inhibitor of Tat cofactor P-TEFb, plays a role in transcriptional latency in T cells. Design and methods The association of 7SK snRNA with P-TEFb was investigated in resting and activated peripheral blood lymphocytes (PBLs). Primary PBLs were isolated by standard methods and activated with phytohemagglutinin (PHA). Levels of 7SK snRNA were determined by Northern blotting and levels of the P-TEFb subunits cyclin-dependent kinase 9 and cyclin T1 were analyzed by immunoblotting. Results The association of 7SK snRNA with P-TEFb complexes was specific. Following activation of PBLs, the levels of 7SK snRNA increased in a manner similar to U1 and U6 snRNA, sn RNAs involved in positive aspects of cellular gene expression. Unexpectedly, the association of 7SK snRNA with P-TEFb increased dramatically following lymphocyte activation. Conclusion Increased association of 7SK snRNA with P-TEFb in activated lymphocytes correlates with increased global transcription. This suggests that 7SK snRNA is unlikely to promote transcriptional latency in lymphocytes through an association with P-TEFb; it also suggests that the proposal that the association of 7SK snRNA with P-TEFb acts to inhibit transcriptional elongation needs to be re-evaluated. |
| Databáze: | OpenAIRE |
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