= T. Ulmasov
{c}
<T. Ulmasov> is the first author credited in a 1997 study of <auxin>-responsive <gene expression> at the University of Missouri. The work introduced the highly active synthetic <DR5 auxin response element> and investigated repression by <Aux IAA proteins>.<Aux IAA proteins repress expression of reporter genes containing natural and highly active synthetic auxin response elements by T. Ulmasov and others>[Original indexed byline and affiliation; Abstract, DR5 construction and repression]{ref}
The experimental idea was to connect a controllable <DNA> sequence to a measurable <reporter gene>. Tandem repeats of an eleven-base-pair unit, including the auxin-responsive sequence `TGTCTC`, produced DR5. The authors tested reporter responses in carrot <protoplasts> and <Arabidopsis thaliana> seedlings. They also tested specific binding of an <auxin response factor> and the effects of increased <Aux IAA proteins> on reporter expression.<Aux IAA proteins repress expression of reporter genes containing natural and highly active synthetic auxin response elements by T. Ulmasov and others>[Abstract, synthetic sequence, expression assays, ARF1 binding and cotransfection]{ref}
A constructed <reporter assay> example illustrates the logic. Suppose a control construct gives activity $1$ without added <auxin> and $8$ with it. A comparison condition gives $0.5$ and $2$. The induction ratios are $8/1=8$ and $2/0.5=4$, while the activities with added auxin differ fourfold. Baseline expression, induced expression and fold induction answer different questions. These invented values illustrate analysis, not the study's measured results.
A <reporter gene> measures an output of the regulatory system under the chosen conditions. A bright DR5 signal is therefore evidence about <auxin>-responsive <gene expression>, not automatically a calibrated local measurement of the <auxin> concentration. Ulmasov and colleagues' contribution supplied a reusable experimental readout together with evidence connecting <auxin response elements>, <transcription factors> and repression.<Aux IAA proteins repress expression of reporter genes containing natural and highly active synthetic auxin response elements by T. Ulmasov and others>[Abstract, reporter utility and interaction experiments]{ref}
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