Gene regulation is a complex process that orchestrates the precise timing and location of both gene activation and gene silencing. Genomic imprinting is a specialized mechanism whereby a gene displays silencing of one parental allele. The imprinted region on human chromosome 11p15.5 and its homologous domain in the mouse consists of a cluster of genes that are silenced on the paternal chromosome by an antisense non-coding RNA, Kcnq1ot1. Very little is known of the molecular mechanisms involved in allele-specific silencing and the role of the non-coding RNAs in modulating this process. This proposal will first exploit transgenic RNA interference technology to test the role of Kcnq1ot1 in establishing imprinting at this locus. In the second and third aims, we will study the epigenetic processes that allow some genes to escape silencing, applying a combination of bioinformatic, biochemical and in vivo approaches to identify regulatory elements in this domain that interact physically and create transcriptionally active domains interspersed with the silenced regions. Identifying the molecular mechanisms underlying the establishment and maintenance of imprinting will advance our understanding of human growth defects and disease.

Public Health Relevance

Genes in the imprinted Kcnq1 domain are involved in Beckwith-Wiedemann syndrome, which causes prenatal overgrowth and predisposition to cancer. Loss of imprinting has been implicated in several human neoplasias. This proposal will provide a more thorough understanding of the regulatory mechanisms deployed in allele-specific gene silencing and will give insight into how these mechanisms can go awry in human disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM093066-02
Application #
8306897
Study Section
Molecular Genetics B Study Section (MGB)
Program Officer
Carter, Anthony D
Project Start
2011-09-01
Project End
2016-08-31
Budget Start
2012-09-01
Budget End
2013-08-31
Support Year
2
Fiscal Year
2012
Total Cost
$290,700
Indirect Cost
$100,700
Name
Temple University
Department
Miscellaneous
Type
Schools of Medicine
DUNS #
057123192
City
Philadelphia
State
PA
Country
United States
Zip Code
19122
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