A Bruno-like gene is required for stem cell maintenance in planarians
A Bruno-like gene is required for stem cell maintenance in planarians
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DOI：
10.1016/j.devcel.2006.06.004
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发表时间：
2006-08-01
影响因子：
11.8
通讯作者：
Newmark, Phillip A.
中科院分区：
文献类型：
--
作者：
Guo, Tingxia;Peters, Antoine H. F. M.;Newmark, Phillip A.
淡水涡虫的再生能力基于成体未分化细胞（neoblasts），这是一种在动物一生当中都存在的干细胞。我们发现RNA结合蛋白Brunolike家族的一个成员对于调节地中海涡虫（Schmidtea mediterranea）的成体未分化细胞至关重要。Smed - bruno - like（bruli）mRNA和蛋白质在成体未分化细胞以及中枢神经系统中表达。在进行bruli RNA干扰（RNAi）之后（这种干扰会消除可检测到的Bruli蛋白），涡虫会启动对截肢的增殖反应并形成小的芽基，但随后会发生组织退化和溶解。我们利用识别SMEDWI - 1和组蛋白H4（单甲基 - K20）的抗体以及细胞周期标记物来标记成体未分化细胞及其后代的亚群，从而对成体未分化细胞群进行特征描述。bruli基因敲低会导致成体未分化细胞大幅减少/消失。我们的分析表明，缺乏Bruli的成体未分化细胞能够对伤口刺激做出反应并产生能够形成芽基和分化的后代；然而，它们无法自我更新。这些结果表明Bruli是干细胞维持所必需的。
The regenerative abilities of freshwater planarians are based on neoblasts, stem cells maintained throughout the animal's life. We show that a member of the Brunolike family of RNA binding proteins is critical for regulating neoblasts in the planarian Schmidtea mediterranea. Smed-bruno-like (bruli) mRNA and protein are expressed in neoblasts and the central nervous system. Following bruii RNAi, which eliminates detectable Bruli protein, planarians initiate the proliferative response to amputation and form small blastemas but then undergo tissue regression and lysis. We characterize the neoblast population by using antibodies recognizing SMEDWI-1 and Histone H4 (monomethyl-K20) and cell-cycle markers to label subsets of neoblasts and their progeny. bruli knockdown results in a dramatic reduction/elimination of neoblasts. Our analyses indicate that neoblasts lacking Bruli can respond to wound stimuli and generate progeny that can form blastemas and differentiate; yet, they are unable to-self-renew. These results suggest that Bruli is required for stem cell maintenance.