B IOL O G Y
QUESTION How does RNA decay contribute to gene expression?
associated with overgrowth in the size of the body or
Could the RNA decay rate be regulated on a molecular
a body part of infants. The condition is almost always
basis in order to control genetic traits?
fatal prior to birth. The disorder has been grouped
Gene expression is typically measured as messenger RNA (mRNA) abundance, and changes in that abundance are usually attributed to transcription,
Plant Genomics Yield Surprising Results LESLIE SIEBURTH
with Renal cell carcinoma and an increased risk for Wilms tumor. Starting in 2014, Sieburth investigated how
or synthesis, of mRNA inside the cell. However,
mRNA decapping and SOV/DIS3L2 contribute to
RNA abundance is also influenced by its disposal,
decay of all mRNAs using genome-wide approaches.
or degradation, but how degradation controls RNA abundance is not well understood.
“A fruitful collaboration with Fred Adler, a professor of biology and mathematics at the U, one of his graduate students, Katrina Johnson, and my
WHO “My research uses a plant model, Arabidopsis thaliana, a small mustard plant, and we found that mutants with defects in mRNA decapping proteins
postdoc Reed Sorenson, identified the decay rates of more than 17,000 mRNAs, and the contributions from decapping and SOV/DIS3L2,” says Sieburth. One unexpected discovery was that the mRNAs
experienced abnormal cell growth,” says Leslie
that decay the fastest use the mRNA decapping
Sieburth, Professor of Biological Sciences at the U.
pathway. A second discovery was that Arabidopsis
“Our curiosity about why the mutants showed such poor growth led us to discover another mRNA decay enzyme, which we call SOV. We noted in our publication, in 2010, that most eukaryotic genomes encode a very similar protein, including humans,” says Sieburth. A few years later, in 2013, scientists studying a human disorder called Perlman syndrome discovered that it was caused by mutations in the same gene. The gene, SOV, is known as DIS3L2 in humans.
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Perlman syndrome is a genetic disorder
mutants lacking an active SOV initiate a feedback
