21067947
not annotated - annotated - LINNAEUS only
Characterizing the role of RNA silencing components in Cryptococcus neoformans.
The RNA interference (RNAi) mediated by homology-dependent degradation of the target mRNA with small RNA molecules plays a key role in controlling transcription and translation processes in a number of eukaryotic organisms. The RNAi machinery is also evolutionarily conserved in a wide variety of fungal species, including pathogenic fungi. To elucidate the physiological functions of the RNAi pathway in Cryptococcus neoformans that causes fungal meningitis, here we performed genetic analyses for genes encoding Argonaute (AGO1 and AGO2), RNA-dependent RNA polymerase (RDP1), and Dicers (DCR1 and DCR2) in both serotype Aserotype A and D C. neoformans. The present study shows that Ago1, Rdp1, and Dcr2 are the major components of the RNAi process occurring in C. neoformans. However, the RNAi machinery is not involved in regulation of production of two virulence factors (capsule and melanin), sexual differentiation, and diverse stress response. Comparative transcriptome analysis of the serotype A and D RNAi mutants revealed that only modest changes occur in the genome-wide transcriptome profiles when the RNAi process was perturbed. Notably, the serotype D rdp1Delta mutants showed an increase in transcript abundance of active retrotransposons and transposons, such as T2 and T3, the latter of which is a novel serotype D-specific transposon of C. neoformans. In a wild type background both T2 and T3 were found to be weakly active mobile elements, although we found no evidence of Cnl1 retrotransposon mobility. In contrast, all three transposable elements exhibited enhanced mobility in the rdp1Delta mutant strain. In conclusion, the RNAi pathway plays an important role in controlling transposon activity and genome integrity of C. neoformans.
Ann file
T1 Species 55 78 Cryptococcus neoformans
N1 Reference T1 Taxonomy:5207
T2 Species 487 510 Cryptococcus neoformans
N2 Reference T2 Taxonomy:5207
T3 Species 695 705;712 725 serotype A C. neoformans
N3 Reference T3 Taxonomy:5207
T4 Species 835 848 C. neoformans
N4 Reference T4 Taxonomy:5207
T5 Species 1427 1440 C. neoformans
N5 Reference T5 Taxonomy:5207
T6 Species 1815 1828 C. neoformans
N6 Reference T6 Taxonomy:5207
T7 Species 695 703;710 725 serotype D C. neoformans
N7 Reference T7 Taxonomy:5207