Medicine and Health Sciences Commons^™

Activating Transcription Factor 3 Promotes Loss Of The Acinar Cell Phenotype In Response To Cerulein-Induced Pancreatitis In Mice, Elena N Fazio, Claire C Young, Jelena Toma, Michael Levy, Kurt R Berger, Charis L Johnson, Rashid Mehmood, Patrick Swan, Alphonse Chu, Sean P Cregan, F Jeffrey Dilworth, Christopher J Howlett, Christopher L Pin

Paediatrics Publications

Pancreatitis is a debilitating disease of the exocrine pancreas that, under chronic conditions, is a major susceptibility factor for pancreatic ductal adenocarcinoma (PDAC). Although down-regulation of genes that promote the mature acinar cell fate is required to reduce injury associated with pancreatitis, the factors that promote this repression are unknown. Activating transcription factor 3 (ATF3) is a key mediator of the unfolded protein response, a pathway rapidly activated during pancreatic insult. Using chromatin immunoprecipitation followed by next-generation sequencing, we show that ATF3 is bound to the transcriptional regulatory regions of >30% of differentially expressed genes during the initiation of pancreatitis. …

Mosaic Expression Of Atrx In The Mouse Central Nervous System Causes Memory Deficits, Renee J Tamming, Jennifer R Siu, Yan Jiang, Marco A M Prado, Frank Beier, Nathalie G Bérubé

Paediatrics Publications

The rapid modulation of chromatin organization is thought to play a crucial role in cognitive processes such as memory consolidation. This is supported in part by the dysregulation of many chromatin-remodelling proteins in neurodevelopmental and psychiatric disorders. A key example is ATRX, an X-linked gene commonly mutated in individuals with syndromic and nonsyndromic intellectual disability. The consequences of Atrx inactivation for learning and memory have been difficult to evaluate because of the early lethality of hemizygous-null animals. In this study, we evaluated the outcome of brain-specific Atrx deletion in heterozygous female mice. These mice exhibit a mosaic pattern of ATRX …

Molecular Characterization Of Nrxn1 Deletions From 19,263 Clinical Microarray Cases Identifies Exons Important For Neurodevelopmental Disease Expression, Chelsea Lowther, Marsha Speevak, Christine M Armour, Elaine S Goh, Gail E Graham, Chumei Li, Susan Zeesman, Malgorzata J M Nowaczyk, Lee-Anne Schultz, Antonella Morra, Rob Nicolson, Peter Bikangaga, Dawa Samdup, Mostafa Zaazou, Kerry Boyd, Jack H Jung, Victoria Siu, Manjulata Rajguru, Sharan Goobie, Mark A Tarnopolsky, Chitra Prasad, Paul T Dick, Asmaa S Hussain, Margreet Walinga, Renske G Reijenga, Matthew Gazzellone, Anath C Lionel, Christian R Marshall, Stephen W Scherer, Dimitri J Stavropoulos, Elizabeth Mccready, Anne S Bassett

Paediatrics Publications

PURPOSE: The purpose of the current study was to assess the penetrance of NRXN1 deletions.

METHODS: We compared the prevalence and genomic extent of NRXN1 deletions identified among 19,263 clinically referred cases to that of 15,264 controls. The burden of additional clinically relevant copy-number variations (CNVs) was used as a proxy to estimate the relative penetrance of NRXN1 deletions.

RESULTS: We identified 41 (0.21%) previously unreported exonic NRXN1 deletions ascertained for developmental delay/intellectual disability that were significantly greater than in controls (odds ratio (OR) = 8.14; 95% confidence interval (CI): 2.91-22.72; P < 0.0001). Ten (22.7%) of these had a second clinically relevant CNV. Subjects with a deletion near the 3' end of NRXN1 were significantly more likely to have a second rare CNV than subjects with a 5' NRXN1 deletion (OR = 7.47; 95% CI: 2.36-23.61; P = 0.0006). The prevalence of intronic NRXN1 deletions was not statistically different between cases and controls (P = 0.618). The majority (63.2%) of intronic NRXN1 deletion cases had a second rare CNV at a prevalence twice as high as that for exonic NRXN1 deletion cases (P = 0.0035).

CONCLUSIONS: The results support the importance of exons …