Iron Homeostasis in Insect Physiology

Iron is a vital micronutrient in insects, serving as a catalytic centre in enzymes that drive respiration, DNA synthesis and detoxification. Unlike vertebrates, insects lack a dedicated hormonal axis for systemic iron regulation, instead relying on cellular and tissue-level networks. Dietary iron is absorbed by midgut epithelial cells, shuttled through the haemolymph largely bound to transferrin and ferritin, and stored within the endomembrane system of the fat body and other organs. Intracellularly, tight control of labile iron pools prevents the formation of reactive oxygen species, while iron-sulphur cluster biogenesis and heme synthesis pathways fulfil essential metabolic demands. Insect immune responses also exploit iron sequestration to limit pathogen growth, and developmental programmes integrate iron availability with moulting, metamorphosis and cuticle formation. Recent insights have revealed that vesicular transport, non-canonical iron sensors and tissue-specific transporters together sustain iron distribution, ensuring both organismal homeostasis and adaptation to environmental challenges.

Research from Nature Portfolio

Recent studies have illuminated critical regulators of intracellular iron traffic and sensing. One investigation demonstrated that a Rab11-GTPase-activating protein orchestrates endosomal recycling of transferrin-1 and ferritin, enabling prothoracic gland cells to acquire iron for steroid cofactor synthesis; loss of this regulator impairs heme production and delays development unless ferritin is supplied exogenously. Another study uncovered that a branching enzyme conventionally linked to glycogen metabolism binds holo-Iron Regulatory Protein 1 (IRP1) and a repair factor, facilitating nuclear entry of IRP1 and pre-emptively downregulating iron-dependent genes as iron requirements wane. This finding reveals an unanticipated role for holo-IRP1 beyond aconitase activity, acting as a transcriptional throttle to anticipate shifts in cellular iron status.

Iron Homeostasis in Insect Physiology publication trend

The graph below shows the total number of articles in iron homeostasis in insect physiology across all publications each year (not limited to Nature Index journals).

Technical terms

Ferritin: A multimeric protein complex that stores iron in a soluble, non-toxic form within cells.

Transferrin: A soluble glycoprotein that binds and transports iron through the haemolymph to target tissues.

Iron Regulatory Protein 1 (IRP1): A bifunctional sensor that switches between aconitase enzyme and RNA-binding activities to regulate iron metabolism genes.

Ferroptosis: A form of iron-dependent cell death driven by lipid peroxidation and oxidative stress.

Entoferritin: Insect-derived ferritin proposed as a dietary iron supplement with high bioavailability.

References

1. Drosophila Evi5 is a critical regulator of intracellular iron transport via transferrin and ferritin interactions. Nature Communications (2024).
2. Glycogen branching enzyme controls cellular iron homeostasis via Iron Regulatory Protein 1 and mitoNEET. Nature Communications (2019).
3. Ironing out the Details: Exploring the Role of Iron and Heme in Blood-Sucking Arthropods. Frontiers in Physiology (2018).
4. Ferritin heavy chain protects the developing wing from reactive oxygen species and ferroptosis. PLOS Genetics (2019).
5. Entoferritin: An innovative iron source for human consumption. Journal of Functional Foods (2023).