Escaping the nuclear confines: Signal-dependent Pre-mRNA splicing in anucleate platelets
Escaping the nuclear confines: Signal-dependent Pre-mRNA splicing in anucleate platelets
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DOI：
10.1016/j.cell.2005.06.015
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发表时间：
2005-08-12
期刊：
影响因子：
64.5
通讯作者：
Weyrich, AS
中科院分区：
文献类型：
--
作者：
Denis, MM;Tolley, ND;Weyrich, AS
血小板是一种特殊的止血细胞，以无核细胞质的形式在血液中循环。我们报告说，血小板出乎意料地具有功能性剪接体，这是一种在其他细胞类型的细胞核中处理前 mRNA 的复合物。剪接体成分存在于人类巨核细胞的细胞质和从巨核细胞延伸的前血小板中。原代人血小板还含有必需的剪接体因子，包括小核 RNA、剪接蛋白和内源性前 mRNA。为了响应整合素结合和表面受体激活，血小板精确地从白细胞介素 1 β 前体 mRNA 中切除内含子，产生可翻译成蛋白质的成熟信息。信号依赖性剪接是血小板的一种新功能，它证明了这种无核细胞的调节功能具有显着的专业性。虽然这种机制可能是血小板所独有的，但它也表明了关于真核细胞中剪接体功能作用的先前未被认识的多样性。
Platelets are specialized hemostatic cells that circulate in the blood as anucleate cytoplasts. We report that platelets unexpectedly possess a functional spliceosome, a complex that processes pre-mRNAs in the nuclei of other cell types. Spliceosome components are present in the cytoplasm of human megakaryocytes and in proplatelets that extend from megakaryocytes. Primary human platelets also contain essential spliceosome factors including small nuclear RNAs, splicing proteins, and endogenous pre-mRNAs. In response to integrin engagement and surface receptor activation, platelets precisely excise introns from interleukin-1 beta pre-mRNA, yielding a mature message that is translated into protein. Signal-dependent splicing is a novel function of platelets that demonstrates remarkable specialization in the regulatory repertoire of this anucleate cell. While this mechanism may be unique to platelets, it also suggests previously unrecognized diversity regarding the functional roles of the spliceosome in eukaryotic cells.