The SMARCAD1-orthologue Fft2 is a novel RNA binder and linked to the nuclear RNA exosome

Abstract

In this study, the role of Fft2, a member of the SMARCAD1 family, is investigated for the ability of posttranscriptional regulation an nuclear RNA exosome interaction in the model organism S. pombe. Using a combination of functional and biochemical approaches, a novel RNA-binding activity mediated by the N-terminal extension was demonstrated for Fft2. It was also shown that Fft2 is recruited to specific chromatin regions in an exosome-dependent manner and that this recruitment is negatively affected by mutations of the exosome components Rrp6 and Mtl1. The author also demonstrated that Fft2 is recruited in an Rrp6-dependent manner to long terminal repeats (LTRs). He also shows that deletion of Fft2 accelerates spore formation but does not lead to impaired chromosome segregation. However, the members of the Fft family show a diverse response to environmental factors, suggesting a functional division of tasks. Overall, this work provides new insights into the role of Fft2, its connection to exosome-dependent regulation of gene expression in S. pombe and a potential crosstalk between the SMARCAD1 family and RNA metabolism.