AUTHOR=Barakate Abdellah , Arrieta Mikel , Macaulay Malcolm , Vivera Sebastian , Davidson Diane , Stephens Jennifer , Orr Jamie , Schreiber Miriam , Ramsay Luke , Halpin Claire , Waugh Robbie 

TITLE=Downregulation of Barley Regulator of Telomere Elongation Helicase 1 Alters the Distribution of Meiotic Crossovers

JOURNAL=Frontiers in Plant Science

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2021.745070

DOI=10.3389/fpls.2021.745070

ISSN=1664-462X

ABSTRACT=<p>Programmed meiotic DNA double-strand breaks (DSBs), necessary for proper chromosomal segregation and viable gamete formation, are repaired by homologous recombination (HR) as crossovers (COs) or non-crossovers (NCOs). The mechanisms regulating the number and distribution of COs are still poorly understood. The regulator of telomere elongation helicase 1 (RTEL1) DNA helicase was previously shown to enforce the number of meiotic COs in <italic>Caenorhabditis elegans</italic> but its function in plants has been studied only in the vegetative phase. Here, we characterised barley <italic>RTEL1</italic> gene structure and expression using RNA-seq data previously obtained from vegetative and reproductive organs and tissues. Using RNAi, we downregulated <italic>RTEL1</italic> expression specifically in reproductive tissues and analysed its impact on recombination using a barley 50k iSelect SNP Array. Unlike in <italic>C. elegans</italic>, in a population segregating for <italic>RTEL1</italic> downregulated by RNAi, high resolution genome-wide genetic analysis revealed a significant increase of COs at distal chromosomal regions of barley without a change in their total number. Our data reveal the important role of RTEL1 helicase in plant meiosis and control of recombination.</p>