SGER: Epigenetic Consequences of Telomere Dysfunction In Plants

Texas A&M Research Foundation, College Station TX

Investigators

Abstract

0104339 Dorothy Shippen Telomeres are essential for genome stability and continued proliferation in an undifferentiated and dedifferentiated state. Arabidopsis thaliana is a useful model to elucidate the role of telomeres in plant growth and development and to address fundamental questions of telomere function in higher eukaryotes. The investigator recently demonstrated that Arabidopsis can survive up to ten generations without telomerase, the enzyme responsible for maintaining tracts of telomeric DNA on chromosome ends. In telomerase-deficient plants, telomeres shorten progressively and late generation mutants endure increasing levels of cytogenetic damage, correlated with developmental anomalies in vegetative and reproductive organs. Unexpectedly, a significant subset of telomerase-deficient plants show a different phenotype that includes homeotic transformation in floral organs and leaves that curl up along the longitudinal axis. The striking similarity of this phenotype to mutants defective in aspects of chromatin structure in Arabidopsis strongly suggests that telomere dysfunction can lead to global epigenetic repercussions in the regulation of gene expression. This project will test whether telomere erosion is accompanied by changes in nuclear architecture and chromatin structure and to reveal the global transcription profile during successive generations of a telomerase deficiency.