Abstract
Tall fescue (Lolium arundinaceum) is one of the primary forage and turf grasses in temperate regions of the world. A number of favourable characteristics of tall fescue are enhanced by its seed-transmissible fungal symbiont (endophyte) Epichloë coenophiala. Our approach was to assemble the tall fescue transcriptome, then identify differentially expressed genes (DEGs) for endophyte-symbiotic (E+) vs endophyte-free (E−) clones in leaf blades, pseudostems, crowns and roots. RNA-seq reads were used to construct a tall fescue reference transcriptome and compare gene expression profiles. Over all tissues examined, 478 DEGs were identified between the E+ and E− clones for at least one tissue (more than two-fold; P < 0.0001, 238 E+ > E− and 240 E− > E+), although no genes were differentially expressed in all four tissues. Gene ontology (GO) terms, GO:0010200 (response to chitin), GO:0002679 (respiratory burst during defence response) and GO:0035556 (intracellular signal transduction) were significantly overrepresented among 25 E− > E+ DEGs in leaf blade, and a number of other DEGs were associated with defence and abiotic response. In particular, endophyte effects on various WRKY transcription factors may have implications for symbiotic stability, endophyte distribution in the plant, or defence against pathogens.
| Original language | English |
|---|---|
| Pages (from-to) | 324-337 |
| Number of pages | 14 |
| Journal | New Phytologist |
| Volume | 213 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jan 1 2017 |
Bibliographical note
Publisher Copyright:No claim to original US government works. New Phytologist © 2016 New Phytologist Trust
Funding
The authors wish to acknowledge Troy Bass for glasshouse care, Walter Hollin and Courtney Frantom for technical support in the laboratory, and John Fellers and Carolyn Young for reviews on an earlier draft of this manuscript. This work was supported by the United States Department of Agriculture – Agricultural Research Service (CRIS project nos. 5042-21000-002-00D and 5030-21220-005-00D) and Special Cooperative Agreement grant 2013-07022058. All of the RNA-seq datasets utilized in the experiment and Fasta file of the TF153K assembly are available at NCBI (BioProject PRJNA284541). This is publication number 16-12-066 of the Kentucky Agricultural Experiment Station, published with the approval of the director. Mention of trade names or commercial products is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the USDA.
| Funders | Funder number |
|---|---|
| NCBI | 16-12-066, PRJNA284541 |
| United States Department of Agriculture-Agricultural Research Service | 2013-07022058, 5030-21220-005-00D, 5042-21000-002-00D |
| U.S. Department of Agriculture | |
| Kentucky Agricultural Experiment Station |
Keywords
- Epichloë coenophiala
- Lolium arundinaceum
- RNA-seq
- differential expression
- transcriptome
ASJC Scopus subject areas
- Physiology
- Plant Science