Myc regulates programmed cell death and radial glia dedifferentiation after neural injury in an echinoderm

BMC Developmental Biology

José E García-Arrarás¹  Olga R Zueva¹  Vladimir S Mashanov¹ 

[1] University of Puerto Rico, Rio Piedras, PO Box 70377, San Juan, PR 00936-8377, USA

关键词: Cell death;    Dedifferentiation;    Central nervous system;    Regeneration;    Myc;   

Others  :  1209033
DOI  :  10.1186/s12861-015-0071-z

 received in 2015-02-20, accepted in 2015-05-01,  发布年份 2015

【 摘 要 】

Background

Adult echinoderms can completely regenerate major parts of their central nervous system even after severe injuries. Even though this capacity has long been known, the molecular mechanisms that drive fast and complete regeneration in these animals have remained uninvestigated. The major obstacle for understanding these molecular pathways has been the lack of functional genomic studies on regenerating adult echinoderms.

Results

Here, we employ RNA interference-mediated gene knockdown to characterize the role of Myc during the early (first 48 hours) post-injury response in the radial nerve cord of the sea cucumber Holothuria glaberrima. Our previous experiments identified Myc as the only pluripotency-associated factor, whose expression significantly increased in the wounded CNS. The specific function(s) of this gene, however, remained unknown. Here we demonstrate that knockdown of Myc inhibits dedifferentiation of radial glia and programmed cell death, the two most prominent cellular events that take place in the regenerating sea cucumber nervous system shortly after injury.

Conclusions

In this study, we show that Myc overexpression is required for proper dedifferentiation of radial glial cells and for triggering the programmed cell death in the vicinity of the injury. Myc is thus the first transcription factor, whose functional role has been experimentally established in echinoderm regeneration.

【 授权许可】

   
2015 Mashanov et al.; licensee BioMed Central.

【 图 表 】

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