Abstract Detail

Poster Session

Hutchinson, Miriam [1], Powell, Amy J. [2], Tsang, Adrian [3], Berka, Randy M. [4], Grigoriev, Igor [5], Barry, Kerrie [5], Natvig, Donald O. [1].

What genome sequences from members of the Chaetomiaceae tell us about the evolution of reproductive systems and thermophily.

The genome sequences of multiple thermophilic and mesophilic members of the Chaetomiaceae (Sordariales) have been acquired as part of an effort to identify evolutionary events that have shaped reproductive and life-style differences among species in the family, including the origin of thermophily in one or more lineages. To date, these genomes have enabled an investigation of the genetics underlying diverse mating systems of the group. When compared with heterothallic species of Neurospora (Sordariaceae), Myceliophthora heterothallica, the only heterothallic species that has been examined from the Chaetomiaceae, possesses mating regions that are conserved with respect to gene content, gene order and orientation. Like heterothallic species of Neurospora, M. heterothallica mating-type a strains have a true mat a-1 ortholog, whereas mating-type A strains possess mat A1-3 genes but not mat a-1. Among members of the Chaetomiaceae with teleomorphic states, heterothallism is rare while homothallism appears to be the norm. Analysis of the genomes of several homothallic species--Chaetomium globosum, C. thermophilum, Thielavia hyrcaniae and T. appendiculata--demonstrates that they possess a true mat a-1 gene, but it is not linked to the mat A-1 region. Among filamentous Ascomycota, this represents one of the recurring evolutionary pathways from heterothallism to homothallism, which requires mat A and mat a regions to be present in one haploid genome. Phylogenetic analyses are in progress to clarify where thermophily has arisen in the family and to help resolve long-standing taxonomic problems that have plagued the group.

1 - University of New Mexico, Department of Biology, Castetter Hall, Albuquerque, New Mexico, 87131, United States
2 - Sandia National Laboratories, 1515 Eubank, Albuquerque, NM, 87123, USA
3 - Concordia University, Centre for Structural and Functional Genomics, Montreal, QC, H4B 1R6, Canada
4 - Novozymes Inc., 1445 Drew Ave, Davis, CA, 95618, USA
5 - DOE Joint Genome Institute, 2800 Mitchell Dr, Walnut Creek, CA, 94598, United States

Keywords:
Chaetomiaceae
Thermophile
Mating systems
Myceliophthora heterothallica
Homothallism.

Presentation Type: Offered Paper - Poster
Session: P2
Location: Lincoln Room/Kellogg Hotel and Conference Center
Date: Tuesday, June 10th, 2014
Time: 8:00 PM
Number: P2011
Abstract ID:168
Candidate for Awards:Graduate Student Poster Presentation Award