Dataset Information

Zfp423 Regulates Sonic Hedgehog Signaling via Primary Cilium Function.

ABSTRACT: Zfp423 encodes a 30-zinc finger transcription factor that intersects several canonical signaling pathways. Zfp423 mutations result in ciliopathy-related phenotypes, including agenesis of the cerebellar vermis in mice and Joubert syndrome (JBTS19) and nephronophthisis (NPHP14) in humans. Unlike most ciliopathy genes, Zfp423 encodes a nuclear protein and its developmental expression is complex, leading to alternative proposals for cellular mechanisms. Here we show that Zfp423 is expressed by cerebellar granule cell precursors, that loss of Zfp423 in these precursors leads to cell-intrinsic reduction in proliferation, loss of response to Shh, and primary cilia abnormalities that include diminished frequency of both Smoothened and IFT88 localization. Loss of Zfp423 alters expression of several genes encoding key cilium components, including increased expression of Tulp3. Tulp3 is a direct binding target of Zfp423 and reducing the overexpression of Tulp3 in Zfp423-deficient cells suppresses Smoothened translocation defects. These results define Zfp423 deficiency as a bona fide ciliopathy, acting upstream of Shh signaling, and indicate a mechanism intrinsic to granule cell precursors for the resulting cerebellar hypoplasia.

SUBMITTER: Hong CJ

PROVIDER: S-EPMC5065120 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Zfp423 Regulates Sonic Hedgehog Signaling via Primary Cilium Function.

Hong Chen-Jei CJ Hamilton Bruce A BA

PLoS genetics 20161011 10

Zfp423 encodes a 30-zinc finger transcription factor that intersects several canonical signaling pathways. Zfp423 mutations result in ciliopathy-related phenotypes, including agenesis of the cerebellar vermis in mice and Joubert syndrome (JBTS19) and nephronophthisis (NPHP14) in humans. Unlike most ciliopathy genes, Zfp423 encodes a nuclear protein and its developmental expression is complex, leading to alternative proposals for cellular mechanisms. Here we show that Zfp423 is expressed by cereb ...[more]

PMID: 27727273

Similar Datasets

Project description:Background:Primary cilia are small non-motile microtubule and cell membrane protrusions expressed on most vertebrate cells, including cortical and hippocampal neurons. These small organelles serve as sensory structures sampling the extracellular environment and reprogramming the transcriptional machinery in response to environmental change. Primary cilia are decorated with a variety of receptor proteins and are necessary for specific signaling cascades such as the Sonic hedgehog (Shh) pathway. Disrupting cilia structure or function results in a spectrum of diseases collectively referred to as ciliopathies. Common to human ciliopathies is cognitive impairment, a symptom also observed in Alzheimer's disease (AD). One hallmark of AD is accumulation of senile plaques composed of neurotoxic Amyloid-? (A?) peptide. The A? peptide is generated by the proteolytic cleavage of the amyloid precursor protein (APP). We set out to determine if A? affects primary cilia structure and the Shh signaling cascade. Methods:We utilized in vitro cell-based assays in combination with fluorescent confocal microscopy to address our study goals. Shh signaling and cilia structure was studied using two different cell lines, mouse NIH3T3 and human HeLa cells. To investigate how A? levels affect Shh signaling and cilia structure in these cells, we utilized naturally secreted A? as well as synthetic A?. Effects on Shh signaling were assessed by luciferase activity while cilia structure was analyzed by fluorescent microscopy. Results:Here, we report that APP localizes to primary cilia and A? treatment results in distorted primary cilia structure. In addition, we demonstrate that A? treatment interrupts canonical Shh signal transduction. Conclusions:Overall, our study illustrates that A? can alter primary cilia structure suggesting that elevated A? levels, like those observed in AD patients, could have similar effects on neuronal primary cilia in the brain. Additionally, our study suggests that A? impairs the Shh signaling pathway. Together our findings shed light on two novel targets for future AD therapeutics.

Dataset Information

Zfp423 Regulates Sonic Hedgehog Signaling via Primary Cilium Function.

Publications

Zfp423 Regulates Sonic Hedgehog Signaling via Primary Cilium Function.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets