Create your own conference schedule! Click here for full instructions

Abstract Detail



Host/Plant Pathogen Interactions and Plant Health Management

Seto, Amanda [1], Donaldson, Michael [2], Saville, Barry [3].

Transcript level assessment in Ustilago maydis teliospores at distinct stages of germination.

Biotrophic basidiomycete fungi cause billions of dollars in damage to North American crops each year. Teliospores are a reproductive and dispersal agent for these fungi and the only cell type capable of completing meiosis. Understanding the molecular events of teliospore germination and the temporally linked meiosis will provide insight regarding disease spread and genetic exchange in these pathogens. The corn smut fungus Ustilago maydis (DC) Corda was used as a model to investigate these processes. RNA-Seq of dormant U. maydis teliospores and those induced to germinate for two different times were used to comprehensively identify genes with changing transcript levels during germination. This approach was limited to finding only those genes in which the change is above the background variation present in the asynchronously germinating teliospore population; however, specific genes and patterns of expression were identified. GO enrichment allowed us to define broad functions of genes with changing transcript levels during germination. To begin linking transcript level changes to morphological events we defined five stages of teliospore germination. In Stage I teliospores have been induced to germinate but are morphologically indistinguishable from dormant teliospores by light microscopy. Stage II teliospores have an emerging promycelium length that is equal to or less than the teliospore diameter. Stage III teliospores have a promycelium length that is longer than the teliospore diameter. Stage IV of germination represents the initial budding of basidiospores, and in Stage V the resulting haploid cells have divided by budding. Multiple approaches were used in an attempt to increase representation of teliospores at distinct stages of germination. These included producing teliospores in highly susceptible inbred corn lines and isolating teliospores from individual tumours, carrying out germination for set times, and separating the different morphological stages of germination by centrifugal elutriation and/or filtration. These techniques were unsuccessful; however, teliospores in Stages I-III of germination can be separated from each other by individual collection using microdissection. The optimization of the microdissection techniques, initial experiments isolating total RNA from 500-1000 teliospores at each of the three germination stages, and assessing transcript level changes of specific genes will be presented along with the RNA-Seq analyses. The goals of this research are to determine a complete description of transcriptome changes during teliospore germination and to identify genes involved in teliospore germination and/or the completion of meiosis.


Log in to add this item to your schedule

Related Links:
The Saville Laboratory


1 - Trent University, Forensic Science Program, 2140 East Bank Drive, DNA Building, Peterborough, ON, K9J 7B8, Canada
2 - Trent University, Environmental and Life Sciences Graduate Program; Forensic Science Program, 2140 East Bank Drive, DNA Building, Rm. A110.3, Peterborough, ON, K9J 7B8, Canada
3 - Trent University, Environmental and Life Sciences Graduate Program; Forensic Science Program, DNA Building, 2140 East Bank Dr, Peterborough, ON, K9J 7B8, Canada

Keywords:
Smut fungi
Meiosis
Dormancy
Spore germination
Microdissection
RNA-Seq.

Presentation Type: Oral Paper:Papers for Topics
Session: 57
Location: Salon 9/The Shaw Conference Centre
Date: Wednesday, July 29th, 2015
Time: 9:30 AM
Number: 57007
Abstract ID:1220
Candidate for Awards:None


Copyright 2000-2015, Botanical Society of America. All rights reserved