Article Alert: Inorganic Phosphate Metabolism Regulated by Novel PXo Bodies in Drosophila

Calcium and phosphorus metabolism in humans is regulated through complex interactions involving bone, the kidneys, and the intestines. In addition, hormones secreted by the thyroid gland (calcitonin) and the parathyroid glands (parathyroid hormone) work in concert with Vitamin D, fibroblast growth factor (FGF23), and other factors to maintain calcium and phosphorus homeostasis (1). Nevertheless, more needs to be known about these physiological processes, particularly those related to phosphate metabolism.

A new study by Xu et al. advances our knowledge of inorganic phosphate (Pi) metabolic regulation in Drosophila melanogaster (2). The authors began their study with the observation that chronic Pi starvation in flies resulted in midgut epithelial hyperproliferation due to downregulation of the Pi transporter PXo. PXo (Pi-sensitive XPR1 orthologue) is a highly conserved Pi transporter responsible for regulating cytosolic Pi levels by transporting Pi into novel multilamellar organelles termed PXo bodies, which disappear with Pi deficiency and require PXo for their formation. Proteomic and lipidomic analyses revealed that PXo bodies serve as an intracellular Pi storage mechanism, and their degradation under conditions of Pi starvation and PXo downregulation acts to boost cytosolic Pi levels. The researchers also found that the STRIPAK complex and JNK signaling component connector of kinase to AP-1 (Cka) mediates the digestive epithelium hyperproliferation. Thus, this study describes the role of PXo bodies in Drosophila Pi metabolism as well as a Pi-dependent PXo-Cka-JNK signaling arc impacting tissue homeostasis.

In response to requests from researchers, GeneTex has expanded its efforts to validate its antibodies for Drosophila sample applications. This includes the GAPDH antibody (GTX100118) cited in the study above. Please see additional Drosophila-validated antibody images below as well as images for some of our reporter protein and epitope tag antibodies. To learn more, please download GeneTex's Drosophila Antibodies flyer and visit www.genetex.com.