Presence and phosphorylation of transcription factors in developing dendrites
Presence and phosphorylation of transcription factors in developing dendrites
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DOI：
10.1073/pnas.95.5.2313
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发表时间：
1998-03-03
影响因子：
11.1
通讯作者：
Eberwine, J
中科院分区：
文献类型：
--
作者：
Crino, P;Khodakhah, K;Eberwine, J
在筛选扩增的多聚腺苷酸mRNA从海马树突和生长锥在文化，以确定候选人的本地翻译，我们发现，选择转录因子mRNA的存在，我们假设，转录因子蛋白质的合成树突内将提供一个直接的信号通路之间的远端树突和细胞核，导致基因表达的调制神经元分化的重要。为了评估这种可能性，我们用放射性标记的扩增的反义RNA探针进行转录因子cDNA的狭缝印迹和锌指转录因子的阵列印迹，检测到编码cAMP反应元件结合蛋白（CREB）、zif 268和一个假定的转录因子的mRNA。我们进一步证实CREB蛋白存在于树突中，CREB mRNA在分离树突中的翻译是可行的，且通过使用原位Southwestern分析，在树突中发现的CREB蛋白质可以与顺式作用环AMP反应元件DNA序列相互作用。此外，树突中的CREB蛋白不从细胞体转运到该位点，因为微灌注到索马中的荧光标记的CREB不扩散到树突中。此外，微灌注到树突中的CREB蛋白被快速转运到核，其可能的生物活性位点。通过使用分离的树突系统，我们表明CREB蛋白上Ser-133的磷酸化可以发生在独立于细胞核的分离的树突中，这些数据提供了一种调节途径，其中在树突中合成和后修饰的转录因子直接改变基因表达，绕过会聚在细胞核上的信号转导途径的整合。
In screening amplified poly(A) mRNA from hippocampal dendrites and growth cones in culture to determine candidates for local translation, we found that select transcription factor mRNAs were present, We hypothesized that synthesis of transcription factor proteins within dendrites would provide a direct signaling pathway between the distal dendrite and the nucleus resulting in modulation of gene expression important for neuronal differentiation. To evaluate this possibility, radiolabelled amplified antisense RNA was used to probe slot blots of transcription factor cDNAs as well as arrayed blots of zinc finger transcription factors, The mRNAs encoding the cAMP response element binding protein (CREB), zif 268, and one putative transcription factor were detected, We expanded upon these results showing that CREB protein is present in dendrites, that translation of CREB mRNA in isolated dendrites is feasible and that CREB protein found in dendrites can interact with the cis-acting cyclic AMP response element DNA sequence by using an in situ Southwestern assay. Further, CREB protein in dendrites is not transported to this site from the cell body because fluorescently tagged CREB microperfused into the soma did not diffuse into the dendrites, In addition, CREB protein microperfused into dendrites was rapidly transported to the nucleus, its likely site of bioactivity, Lastly, by using the isolated dendrite system we show that phosphorylation of Ser-133 on CREB protein can occur in isolated dendrites independent of the nucleus, These data provide a regulatory pathway in which transcription factors synthesized and posttranslationally modified in dendrites directly alter gene expression bypassing the integration of signal transduction pathways that converge on the nucleus.