Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
XB-ART-51795
Dev Biol March 15, 2016; 411 (2): 257-265.

Identifying domains of EFHC1 involved in ciliary localization, ciliogenesis, and the regulation of Wnt signaling.

Zhao Y , Shi J , Winey M , Klymkowsky MW .


Abstract
EFHC1 encodes a ciliary protein that has been linked to Juvenile Myoclonic Epilepsy. In ectodermal explants, derived from Xenopus laevis embryos, the morpholino-mediated down-regulation of EFHC1b inhibited multiciliated cell formation. In those ciliated cells that did form, axoneme but not basal body formation was inhibited. EFHC1b morphant embryos displayed defects in central nervous system (CNS) and neural crest patterning that were rescued by a EFHC1b-GFP chimera. EFHC1b-GFP localized to ciliary axonemes in epidermal, gastrocoele roof plate, and neural tube cells. In X. laevis there is a link between Wnt signaling and multiciliated cell formation. While down-regulation of EFHC1b led to a ~2-fold increase in the activity of the β-catenin/Wnt-responsive TOPFLASH reporter, EFHC1b-GFP did not inhibit β-catenin activation of TOPFLASH. Wnt8a RNA levels were increased in EFHC1b morphant ectodermal explants and intact embryos, analyzed prior to the on-set of ciliogenesis. Rescue of the EFHC1b MO''s ciliary axonemal phenotypes required the entire protein; in contrast, the EFHC1b morpholino''s Wnt8a, CNS, and neural crest phenotypes were rescued by a truncated form of EFHC1b. The EFHC1b morpholino''s Wnt8a phenotype was also rescued by the injection of RNAs encoding secreted Wnt inhibitors, suggesting that these phenotypes are due to effects on Wnt signaling, rather than the loss of cilia, an observation of potential relevance to understanding EFHC1''s role in human neural development.

PubMed ID: 26783883
PMC ID: PMC4892117
Article link: Dev Biol
Grant support: [+]
Genes referenced: cetn4 ctnnb1 dkk1 efhc1 efhc2 egr2 en2 fgf8 nog sfrp2 sox9 tuba4b tubb2b tubb4b twist1 wnt1 wnt8a
Antibodies: Cetn4 Ab1
Morpholinos: efhc1 MO1

Phenotypes: Xla Wt + efhc1 MO (fig.4.b) [+]

Article Images: [+] show captions
References [+] :
Araki, Centrosome protein centrin 2/caltractin 1 is part of the xeroderma pigmentosum group C complex that initiates global genome nucleotide excision repair. 2001, Pubmed


Xenbase: The Xenopus Model Organism Knowledgebase.
Version: 4.15.0
Major funding for Xenbase is provided by grant P41 HD064556