{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nRN7SK functions as a central scaffold for the 7SK small nuclear ribonucleoprotein (snRNP), which plays a pivotal role in regulating transcription elongation by sequestering the positive transcription elongation factor b (P-TEFb). In its inactive state, P-TEFb—composed of CDK9 and a cyclin partner—is bound by 7SK together with inhibitory factors such as HEXIM proteins. Under defined stress conditions or upon signaling events, including the direct engagement of viral proteins like HIV-1 Tat (which binds a conserved stem‐loop element reminiscent of the viral TAR), the 7SK snRNP undergoes compositional and conformational changes that release P-TEFb to stimulate RNA polymerase II activity. Moreover, dynamic phosphorylation and dephosphorylation events, as well as interactions with additional regulators, ensure that P-TEFb is correctly localized (for example in nuclear speckles) and functionally modulated for transcriptional elongation during both normal cellular homeostasis and response to environmental cues."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "1", "end_ref": "17"}]}, {"type": "t", "text": "\n"}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nIn addition to modulating transcription elongation, RN7SK participates in broader gene regulatory networks by interfacing with chromatin remodelers and various RNA‐binding proteins. Through physical interactions with factors such as HMGA1, m6A RNA readers, and components of the little elongation complex, RN7SK not only influences enhancer activity and bidirectional transcription from promoters but also supports the synthesis of RNAPII‐dependent small nuclear and nucleolar RNAs. 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