Genome organisation and expression profiling of ABC protein-encoding genes in Heterobasidion annosum s.l. complex. Issue 3 (March 2016)

• Record Type: Journal Article
• Authors: Baral, Bikash; Kovalchuk, Andriy; Asiegbu, Fred O.
• Is Part Of: Fungal biology. Volume 120:Issue 3(2016:Mar.)
• Page Start: 376
• Page End: 384
• Publication Date: 2016-03
• Subjects: ABC transporter -- Drug resistance -- Efflux pumps -- Gene expression -- Heterobasidion -- Terpenoids; Mycology -- Periodicals; Fungi -- Periodicals; 579.505
• DOI: 10.1016/j.funbio.2015.11.005
• Languages: English
• ISSNs: 1878-6146

Abstract

Abstract: Members of Heterobasidion annosum species complex are widely regarded as the most destructive fungal pathogens of conifer trees in the boreal and temperate zones of Northern hemisphere. To invade and colonise their host trees, Heterobasidion fungi must overcome components of host chemical defence, including terpenoid oleoresin and phenolic compounds. ABC transporters may play an important role in this process participating in the export of toxic host metabolites and maintaining their intracellular concentration below the critical level. We have identified and phylogenetically classified Heterobasidion genes encoding ABC transporters and closely related ABC proteins. The number of ABC proteins in the Heterobasidion genome is one of the lowest among analysed species of Agaricomycotina. Using quantitative RT-PCR, we have analysed transcriptional response of Heterobasidion ABC transporter-encoding genes to monoterpenes as well as their expression profile during growth on pine wood in comparison to the growth on defined media. Several ABC transporters were up-regulated during growth on pine wood. The ABC-transporter encoding gene ABCG1.1 was induced both during growth of H. annosum on pine wood and upon exposure to monoterpenes. Our experimental data demonstrate the differential responses of Heterobasidion ABC genes to growth conditions and chemical stressors. The presented results suggest a potential role of Heterobasidion ABC-G transporters in the resistance to the components of conifer chemical defence. Highlights: Genome-wide inventory has identified 32 ABC genes in the Heterobasidion genome. Identified ABC genes were assigned to eight subfamilies in the phylogenetic analysis. ABC genes were differentially induced upon growth on wood and by chemical stressors. A role for a Heterobasidion ABC-G transporter in terpenoid resistance is proposed.