Repository logo

Tumor protein Tctp regulates axon development in the embryonic visual system.

Published version

Repository DOI

Change log


Roque, Cláudio Gouveia 
Wong, Hovy Ho-Wai 
Lin, Julie Qiaojin 
Holt, Christine E 


The transcript encoding translationally controlled tumor protein (Tctp), a molecule associated with aggressive breast cancers, was identified among the most abundant in genome-wide screens of axons, suggesting that Tctp is important in neurons. Here, we tested the role of Tctp in retinal axon development in Xenopus laevis We report that Tctp deficiency results in stunted and splayed retinotectal projections that fail to innervate the optic tectum at the normal developmental time owing to impaired axon extension. Tctp-deficient axons exhibit defects associated with mitochondrial dysfunction and we show that Tctp interacts in the axonal compartment with myeloid cell leukemia 1 (Mcl1), a pro-survival member of the Bcl2 family. Mcl1 knockdown gives rise to similar axon misprojection phenotypes, and we provide evidence that the anti-apoptotic activity of Tctp is necessary for the normal development of the retinotectal projection. These findings suggest that Tctp supports the development of the retinotectal projection via its regulation of pro-survival signalling and axonal mitochondrial homeostasis, and establish a novel and fundamental role for Tctp in vertebrate neural circuitry assembly.



Axon guidance, Neural circuitry assembly, RNA localisation, Retinal ganglion cell, Retinotectal projection, Tctp, tpt1, Animals, Axons, Biomarkers, Tumor, Blastomeres, Cells, Cultured, Embryo, Nonmammalian, In Situ Nick-End Labeling, Membrane Potential, Mitochondrial, Mitochondria, Mitochondrial Dynamics, Morpholinos, Myeloid Cell Leukemia Sequence 1 Protein, Neurogenesis, Optic Lobe, Nonmammalian, Rats, Rats, Inbred F344, Retina, Retinal Ganglion Cells, Tumor Protein, Translationally-Controlled 1, Visual Pathways, Xenopus laevis

Journal Title


Conference Name

Journal ISSN


Volume Title



The Company of Biologists
Wellcome Trust (085314/Z/08/Z)
This work was supported by Fundação para a Ciência e Tecnologia (C.G.R.; fellowship SFRH/BD/33891/2009), Sir Edward Youde Memorial Fund, Croucher Foundation, Cambridge Commonwealth–European & International Trust (H.W.), Gates Cambridge Scholarship (J.Q.L.), and a Wellcome Trust Programme Grant (C.E.H.; grant 085314/Z/08/Z).