The Dynein Light Chain Tctex-1 Has a Dynein-Independent Role in Actin Remodeling during Neurite Outgrowth

Cell and Developmental Biology, Cornell University, Итак, New York, United States
Developmental Cell (Impact Factor: 9.71). 08/2005; 9(1):75-86. DOI: 10.1016/j.devcel.2005.04.003
Source: PubMed


Coordinated microtubule and microfilament changes are essential for the morphological development of neurons; however, little is know about the underlying molecular machinery linking these two cytoskeletal systems. Similarly, the indispensable role of RhoGTPase family proteins has been demonstrated, but it is unknown how their activities are specifically regulated in different neurites. In this paper, we show that the cytoplasmic dynein light chain Tctex-1 plays a key role in multiple steps of hippocampal neuron development, including initial neurite sprouting, axon specification, and later dendritic elaboration. The neuritogenic effects elicited by Tctex-1 are independent from its cargo adaptor role for dynein motor transport. Finally, our data suggest that the selective high level of Tctex-1 at the growth cone of growing axons drives fast neurite extension by modulating actin dynamics and also Rac1 activity.

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Available from: Cecilia Conde
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    • "DYNLT1 is also implicated in functions independent of the cytoplasmic dynein complex [63]. DYNLT1 was shown to mediate neuritogenesis during hippocampal neuronal development in a dynein-independent manner [64]. It was also identified as an activator of G-protein signaling in association with several receptor proteins like the Trk neurotrophin receptor, bone morphogenetic receptor type II and the parathyroid hormone receptors [65], [66], [67], [68]. "
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    • "The IQGAP1, Arp2, Arp3, N-WASP short hairpin (sh) RNAs and their corresponding scrambled control sequences were constructed using previously described procedures [35], [36]. In brief, DNA fragments containing U6-sh-RNA and U6-scrambled-sh were inserted into pCAG vector in which the GFP or HcRed cDNA is under the control of a chick actin-minimal (CAG) promoter [35], [36]. "
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    • "Li et al. 2011 [63] investigated TCTEX1/DYNLT, a dynein light chain subunit involved in cargo binding but that can also be recruited for functions independent of the dynein complex [64]. Active phosphorylated TCTEX1 was found to be recruited to the ciliary transition zone prior to cilia disassembly and entry into S phase of the cell cycle [63]. "
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