How are proteins addressed to the nucleolus?
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Proteins are addressed to the nucleolus through specific localization signals and a GTP-driven cycle. The localization signals, such as nuclear localization signals (NLS) and nucleolar detention signals regulated by H+ (NoDSH+), guide proteins to the nucleolus . The presence of a GTP switch suggests that nucleolar localization can be regulated and responsive to extracellular stimuli via signaling pathways . Proteins enter the nucleus from the cytoplasm through nuclear pore complexes (NPCs) using facilitated transport factors, including receptors that recognize the NLS and the small GTPase Ran . The nucleolus is a dynamic structure that plays roles in ribosome biogenesis, cell cycle regulation, and stress response, and its proteins are sequestered or released to mediate these functions . The nucleolus provides an ideal electrochemical environment for binding poly-arginine containing proteins, which accumulate in nucleoli through interactions with RNA . The identification of a higher-order and predictive code for nucleolar targeting reveals rules governing subnuclear organization and regulation of proteins .
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| Papers (5) | Insight |
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44 Citations | The paper identifies a common subnuclear targeting consensus sequence, referred to as a nucleolar detention signal regulated by H+ (NoDSH+), that allows proteins to interact with the nucleolus in response to a specific signal. |
99 Citations | The paper discusses that proteins are addressed to the nucleolus through specific sequences called nucleolar localization signals (NoLS) which contain a high content of basic amino acids. |
| The paper discusses the current understanding of nucleolar targeting and the types of sequences that control protein localization to the nucleolus. It suggests that certain subsets of nucleolar proteins may act as hub proteins that can bind to multiple protein targets. However, it does not provide specific details on how proteins are addressed to the nucleolus. | |
5 Citations | The provided paper does not specifically mention how proteins are addressed to the nucleolus. The paper focuses on how proteins are directed to the nucleus through the use of nuclear localization signal (NLS) tags. |
| The paper discusses a GTP-driven cycle as the first true molecular mechanism for nucleolar localization, suggesting that retention, rather than active targeting, determines protein localization in the nucleolus. |
Related Questions
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