Introns do grupo I no mitogenoma de fungos: aspectos evolutivos e sua relevância na micologia médica

Abstract

Group I introns (IGI) are small RNAs (250-500 nt) capable of catalysing their own splicing from the precursor RNA. They are widely distributed across the tree of life and have intricate relationships with their host genomes. In this work we gather information published in the scientific literature and in the MitoFun database about group I mitochondrial introns in Fungi Kingdom, in order to understand, from an evolutionary perspective, the distribution of these elements in genes and genomes and their possible impact on mitochondrial morphology and function, as well as their influence on their host's fitness, concerning virulence and susceptibility to antifungals. The existing literature highlights the relationship between presence and absence of autocatalytic introns with differences in the pattern of mitochondrial fission and fusion, respectively and suggests that strains with more introns in the mitogenome are less virulent and more sensitive to drugs such as 5-fluocytokine and amphotericin B. Our findings confirm the greater presence of these elements in the mitochondrial genes cox1, cob and rnl, both with regard to the number of introns and insertion sites. Interestingly, our data reveal that pathogenic fungi have, on average, less autocatalytic introns than the others, suggesting that the IGI distribution is not sporadic but may be related to fungi lifestyle and to different evolutionary pressures.