Fission yeast RNA‐binding proteins Puf2 and Puf4 are involved in repression of ferrireductase Frp1 expression in response to iron

Abstract

Acquisition of iron is essential to several biochemical processes, including tricarboxylic acid cycle activity, respiration, antioxidant defense, and DNA replication (Galaris et al., 1866;Philpott et al., 2020;Puig et al., 2017). Iron plays a critical role as an electron transfer intermediate for catalytic enzyme activity due to its ability to lose or to gain one electron. On the other hand, when present in excess, iron in its reduced state can react with hydrogen peroxide to produce the highly toxic hydroxyl radical that can damage cellular components (Gutteridge & Halliwell, 2018). Consequently, cells have developed homeostatic mechanisms to acquire adequate, but not excessive, intracellular concentrations of iron.Studies in the model organism Schizosaccharomyces pombe have led to the identification of cellular components that are required to ensure adequate iron assimilation needed for some iron-dependent

Fission Yeast PUF Proteins Puf3 and Puf4 Are Novel Regulators of PI4P5K Signaling

“…A recent study showed that the fission yeast Puf2 and Puf4 regulate iron uptake through frp1 + encoding a key enzyme of the reductive iron uptake pathway. 32) Puf2 and Puf4 may protect cells against toxic levels of iron by binding to the Pumilio response elements (PREs) in the 3′UTR of Frp1 mRNA under basal and iron-replete conditions, and destabilizing Frp1 mRNA. Notably, Its3 mRNA contains a potential canonical PRE sequence (UGUANAUA) in its 3′UTR, 33,34) indicating that Puf3 and Puf4 might be able to directly bind to and regulate Its3 mRNA.…”