The Lotus japonicus Genome

20

Forward and Reverse Genetics: The

LORE1 Retrotransposon Insertion

Mutants

Eigo Fukai, Anna Małolepszy, Niels Sandal, Makoto Hayashi,

and Stig U. Andersen

Abstract

The endogenousLotus retrotransposon 1(LORE1) transposes in the germ

line ofLotus japonicusplants that carry an active element. This feature of

LORE1 has been exploited for generation of a large non-transgenic

insertion mutant population, where insertions have been annotated using

next-generation sequencing approaches. The LORE1mutant lines are

freely available and can be ordered online. Endogenous retrotransposons

are also active in many other plant species. Based on the methods

developed for LORE1mutagenesis, it should be simple to establish

similar systems in other species, once an appropriate element has been

identified.

20.1 Introduction

The interaction between legumes and rhizobia
that allows symbiotic nitrogenfixation has been
extensively studied. Since the 1990s, the
molecular characterization of plant symbiotic
genes has been accelerated by the use of two
model legumes,Lotus japonicusandMedicago
truncatula. Developing genetic tools, such as
mutant collections, will help to expand the

application of model legumes to a wider range of

research areas and will facilitate the identification

of legume genes of agronomical importance.

Next-generation sequencing has greatly

increased the availability of genomic information

for many plant species. To facilitate exploitation

of this information, ready access to loss-of-

function alleles from mutant collections will be

essential in a wide range of plant species,

including legumes. In this chapter, the estab-

lishment of aLotusmutant resource using the

endogenous retrotransposonLotus retrotranspo-

son 1(LORE1) is described along with the fea-

tures of this mutant collection. In addition, future

possibilities for establishing mutant collections in

other legume species are discussed.

A. Małolepszy
N. Sandal
S.U. Andersen (&)
Centre for Carbohydrate Recognition and Signalling,
Department of Molecular Biology and Genetics,
Aarhus University, Gustav Wieds Vej 10, 8000
Aarhus C, Denmark
e-mail: [email protected]

E. Fukai
M. Hayashi
National Institute of Agrobiological Sciences,
Tsukuba 305-8602, Japan

S. Tabata and J. Stougaard (eds.),The Lotus japonicus Genome, Compendium of Plant Genomes,
DOI 10.1007/978-3-662-44270-8_20,©Springer-Verlag Berlin Heidelberg 2014

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