Sexual development in Hypocrea jecorina

01.04.2010 - 31.03.2014
Research funding project
Sexual development is one of the most important achievements in evolution. Fisher and Müller stated already in 1930, that ¿the very existence of sex implies its advantage¿. Not only does it contribute to improvement of the fitness and adaptation of a given organism to its ecological niche, the fact that sexual development is induced if environmental conditions deteriorate, also indicates that this process is of utmost importance for survival of a species. The case of sexuality in the industrial workhorse Trichoderma reesei (anamorph of Hypocrea jecorina) is special in so far as both research as well as industrial strain improvement is solely based on the single isolate QM6a and its (asexual) progeny. The filamentous ascomycete T. reesei QM6a has been isolated during the world war II because it degraded army equipment made of cotton. Later on, the impressive amounts of cellulases this strain secrets, which led to its isolation in the first place, became the focus of research programs. As with all other filamentous fungi applied in industry, the possibility of crossing was not available for T. reesei, although in silico data had identified H. jecorina as its teleomorph more than a decade ago. Recently, we described the two mating type loci of T. reesei (MAT1-1 and MAT1-2) and we were for the first time able to induce sexual reproduction of T. reesei QM6a (MAT1-2) in crossings with a MAT1-1 wild-type isolate of H. jecorina, and we obtained fertilized stromata and mature ascospores . However, a serious issue with our findings was, that while male fertile, T. reesei QM6a is female sterile. In the course of the proposed project I intend to gain first insights into mechanisms related to sexual development in T. reesei. By comparison of the genomes of the female sterile strain QM6a and the fertile wild-type isolate I will select candidate genes presumable responsible for female fertility und confirm their function by deletion in the wild-type strain and complementation of QM6a. Physiological differences between strains of different mating types shall be revealed by analysis of transcription patterns and carbon source utilization patterns. Thereby intriguing insights into adjustment of the biological equilibrium between sexual and asexual development ¿ possibly by slightly different ecological niches of mating partners ¿ will be obtained. On the other hand, these results will contribute to selection and improvement of strains of appropriate mating type for a given application. I will further analyse the interrelationship of two genes, which impact sexual development in opposite ways in order to determine their position in the signaling cascade and their function in H. jecorina. Knowledge on sexual development in H. jecorina, as gained in the course of this project, will not only significantly increase our understanding of physiology of this fungus in nature but also boost research towards environmentally safe and economically reasonable biofuels produced from cellulosic waste material.

People

Project leader

Institute

Grant funds

  • FWF - Österr. Wissenschaftsfonds (National) Austrian Science Fund (FWF)

Research focus

  • Beyond TUW-research focus: 100%

Keywords

GermanEnglish
Hypocrea jecorinaHypocrea jecorina
Sexuelle EntwicklungSexual development
Cellulasencellulases

Publications