Combined Transcriptome Profiling Reveals a Novel Family of Arbuscular Mycorrhizal-Specific Medicago truncatula Lectin Genes

authored by

André Frenzel, Katja Manthey, Andreas M. Perlick, Folker Meyer, Alfred Pühler, Helge Küster, Franziska Krajinski

Abstract

The large majority of plants are capable of undergoing a tight symbiosis with arbuscular mycorrhizal (AM) fungi. During this symbiosis, highly specialized new structures called arbuscules are formed within the host cells, indicating that, during interaction with AM fungi, plants express AM-specific genetic programs. Despite increasing efforts, the number of genes known to be induced in the AM symbiosis is still low. In order to identify novel AM-induced genes which have not been listed before, 5,646 expressed sequence tags (ESTs) were generated from two Medicago truncatula cDNA libraries: a random cDNA library (MtAmp) and a suppression subtractive hybridization (SSH) library (MtGim), the latter being designed to enhance the cloning of mycorrhiza-upregulated genes. In silico expression analysis was applied to identify those tentative consensus sequences (TCs) of The Institute for Genomic Research M. truncatula gene index (MtGI) that are composed exclusively of ESTs deriving from the MtGim or MtAmp library, but not from any other cDNA library of the MtGI. This search revealed 115 MtAmp- or MTGim-specific TCs. For the majority of these TCs with sequence similarities to plant genes, the AM-specific expression was verified by quantitative reverse-transcription polymerase chain reaction. Annotation of the novel genes induced in mycorrhizal roots suggested their involvement in different transport as well as signaling processes and revealed a novel family of AM-specific lectin genes. The expression of reporter gene fusions in transgenic roots revealed an arbuscule-related expression of two members of the lectin gene family, indicating a role for AM-specific lectins during arbuscule formation or functioning.

Organisation(s)

Institute of Plant Genetics

External Organisation(s)

Bielefeld University

Type

Article

Journal

Molecular Plant-Microbe Interactions

Volume

18

Pages

771-782

No. of pages

12

ISSN

0894-0282

Publication date

25.01.2008

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Physiology, Agronomy and Crop Science

Electronic version(s)

https://doi.org/10.1094/MPMI-18-0771 (Access: Open)