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Qu, T.

Publications and source records attributed to Qu, T..

2 recordsLinked to original sources

Phenotypic analysis of catastrophic childhood epilepsy genes: The Epilepsy Zebrafish Project

Genetic engineering techniques have contributed to the now widespread use of zebrafish to investigate gene function, but zebrafish-based human disease studies, and particularly for neurological disorders, are limited. Here we used CRISPR-Cas9 to generate 40 single-gene mutant zebrafish lines representing catastrophic childhood epilepsies. We evaluated larval phenotypes using electrophysiological, behavioral, neuro-anatomical, survival and pharmacological assays. Phenotypes with unprovoked electrographic seizure activity (i.e., epilepsy) were identified in zebrafish lines for 8 genes; ARX, EEF1A, GABRB3, GRIN1, PNPO, SCN1A, STRADA and STXBP1. A unifying epilepsy classification scheme was developed based on local field potential recordings and blinded scoring from ~3300 larvae. We also created an open-source database containing sequencing information, survival curves, behavioral profiles and representative electrophysiology data. We offer all zebrafish lines as a resource to the neuroscience community and envision them as a starting point for further functional analysis and/or identification of new therapies.

neuroscience

Species-specific sensitivity to TGFβ signaling and changes to the Mmp13 promoter underlie avian jaw development and evolution

Developmental control of jaw length is critical for survival. The jaw skeleton arises from neural crest mesenchyme and previously we demonstrated that these progenitors upregulate bone-resorbing enzymes including Matrix metalloproteinase 13 (Mmp13) when generating short quail beaks versus long duck bills. Inhibiting bone resorption or Mmp13 increases jaw length. Here, we uncover mechanisms establishing species-specific levels of Mmp13 and bone resorption. Quail show greater activation of, and sensitivity to Transforming Growth Factor-Beta (TGF{beta}) signaling than duck; where mediators like SMADs and targets like Runx2, which bind Mmp13, become elevated. Inhibiting TGF{beta} signaling decreases bone resorption. We discover a SMAD binding element in the quail Mmp13 promoter not found in duck and single nucleotide polymorphisms (SNPs) near a RUNX2 binding element that affect expression. Switching the SNPs and SMAD site abolishes TGF{beta}-sensitivity in the quail Mmp13 promoter but makes duck responsive. Thus, differential regulation of TGF{beta} signaling and Mmp13 promoter structure underlie avian jaw development and evolution.

developmental biology