Dr. Tom Jongens and Dr. Sean McBride study Fragile X Fruit Flies

Fruit Flies to Model and Test Fragile X Treatments

Dr. Jongens and his collaborators have found an insulin-like protein in the fly brain that is overexpressed in the Fragile X mutant fly, leading to increased activity of the insulin signaling pathway. Furthermore, they found that certain behavioral patterns in the fragile X flies can be rescued by expressing the FX gene just in insulin producing neurons in the fly brain. In the mutant, there are other changes in the signaling pathways, including a decrease in cAMP and elevation in PI3K, mTOR, Akt and ERK activity. They now propose to study 2 medicines used for diabetes: pioglitazone (increases cAMP and decreases Akt and ERK) and metformin (inhibits mTOR), in flies and mice to validate the potential efficacy of these novel therapeutics for Fragile X.

Kimberly Huber, Ph.D., FRAXA Investigator

Evaluation of CamKII Dependent Regulation of mGluR5-Homer Scaffolds as a Potential Therapeutic for Fragile X Syndrome

Dr. Huber made the original discovery of the mGluR Theory of Fragile X when she was a postdoctoral fellow in the lab of Dr. Mark Bear, with her first FRAXA grant in 2000. Dr. Huber has received $474,300 in grants from FRAXA Research Foundation since then, researching molecular mechanisms and developmental switches in fragile X syndrome. She has worked with 4 FRAXA Postdoctoral Fellows (Elena Nosyreva, PhD in 2006; Jennifer Roseni, PhD in 2007; Tong Zang, PhD in 2010-2011; and Weirui Guo, PhD in 2012-2013) and has received supporting funds from The Meadows Foundation of/for Texas.

Involvement of the miRNA Pathway in Fragile X Syndrome

With a $304,000 grant from FRAXA Research Foundation over several years, Drs. Oostra and deVrij from Erasmus University studied miRNA and fragile X. miRNAs are RNAs that can repress the translation of target mRNAs – therefore they can play a role in protein synthesis within the neuron. Preliminary results showed large differences in miRNA expression in the fragile X mouse brain compared to the wild type. This lab investigated the effect of mGluR5 antagonists on the levels of these specific miRNAs.

Basic Mechanisms of Disease and Potential Therapeutic Strategies

With $245,000 in grants from FRAXA Research Foundation, Dr. Stephen Warren and his lab at Emory University studied all aspects of fragile X syndrome, from the mechanisms of repeat expansion to high-throughput drug screens in the Drosophila model of fragile X. The Warren lab made the original discovery of the fragile X gene, FMR1, in collaboration with the Nelson and Oostra labs, and is recognized internationally as a leader in molecular genetics. Recent projects include establishment of induced pluripotent stem cell lines from fragile X patients, and determination of other forms of mutation in the fragile X gene, other than the most common trinucleotide repeat expansion.