Filamentous fungi, such as Aspergillus fumigatus, are characterized by a highly polarized growth that occurs mainly by hyphal tip extension. Fungal tip growth involves many processes such as cell wall synthesis, vesicle transport, exocytosis and endocytosis. Even though there has been a reasonable amount of progress understanding these processes in the past few years, the exact mechanisms that regulate establishment and maintenance of polarity are not completely understood. Recent studies of highly polar cells from Drosophila melanoganster, Candida albicans, Ustilago maydis and others have demonstrated that RNA localization is used to restrict translation spatially and temporally. Consequently, we investigated asymmetric RNA localization in A. fumigatus . Laser microcapture combined with 454 sequencing done in our lab identified many of transcripts that appeared to be asymmetrically localized in polar A. fumigatus cells. In order to validate the level of asymmetry detected by 454 sequencing we performed Fluorescent in situ hybridization (FISH) . Transcripts from tip, base and conidia that showed the greatest asymmetry and the highest expression levels were chosen to synthesize digoxigenin labeled dsDNA probes for in vivo detection in A. fumigatus germlings. FISH experiments confirmed that many individual mRNA's are differentially localized to tip, base and conidium.
Full conference title:
26th Fungal Genetics Conference
- Fungal Genetics Conference 26th (2005)