I am postdoctoral researcher at University of Kansas (KU). Before coming to KU, I finished my doctorate in NABI, India where I explored the molecular mechanism of silicon uptake by plants. Here ate KU, I am trying to understand the evolutionary basis of plant telomeric variations by using Mimulus as a model plant. My research focus is to understand the evolutionary force and molecular mechanism behind the telomeric variations utilizing various species of Mimulus. My ultimate research aim is improving crop varieties, revolutionizing agriculture, fostering sustainable food system and helping growers.
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Monkeyflower (Mimulus) uncovers the molecular and evolutionary mechanism underlying plant telomere sequence variation
S. KUMAWAT, I. MARTINEZ, D. LOGESWARAN, H. CHEN, J. M. COUGHLAN, J. L. CHEN, J. SOBEL, J. Y. CHOI
Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA
Telomere is a nucleoprotein complex that protects chromosome ends from genomic instability. Because of this crucial role, components of the telomere, for instance the DNA sequence, are thought to be under strong evolutionary constraint and prohibited from changing. But in plants, their telomeres display an enormous range of sequence variation and the mechanism that drives the variation is largely unknown. Here, I will present results from Monkeyflower (Mimulus) telomeres and propose a novel model to explain telomere sequence variation in plants. I investigated the Mimulus telomere evolution by studying the telomerase RNA (TR), which is a core telomere maintenance gene and determines the telomere DNA sequence. Through comparative de novo transcriptome analysis of 22 Mimulus species, I discovered Mimulus species has evolved at least three different types of telomere sequences. Unexpectedly, we discovered several Mimulus species with duplicated TR genes and prior to my study all eukaryotes were known to carry only a single TR gene. Evolutionary analysis indicated the duplication had arose from a transposition-mediated mechanism. From my results, I hypothesize transposition and duplication of the TR gene leads to sequence divergence between TR paralogs, resulting in changes and evolutionary turnover in the telomere sequence for Mimulus and potentially all plants.