InsP3 Signaling in Apicomplexan Parasites
Celia R S Garcia1, Eduardo Alves2, Pedro H S Pereira1,2
1Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo. Sao Paulo 05508-090, Brazil
Current Topics in Medicinal Chemistry
|February 1, 2017
Summary
Apicomplexan parasites produce myo-inositol 1,4,5-trisphosphate (InsP3) for calcium signaling, yet lack identified InsP3 receptors (InsP3Rs). This suggests a potential primitive or non-canonical InsP3R, offering therapeutic targets.
Area of Science:
- Cellular Biology
- Parasitology
- Biochemistry
Background:
- Phosphoinositides (PIs) are vital cell membrane components regulating cellular functions.
- Myo-inositol 1,4,5-trisphosphate (InsP3) generation via phospholipase C (PLC) hydrolysis of PIP2 initiates calcium signaling.
- InsP3 acts as a second messenger, triggering intracellular calcium release from the endoplasmic reticulum by binding to InsP3 receptors (InsP3Rs).
Purpose of the Study:
- Investigate the presence and nature of InsP3 receptors in Apicomplexa.
- Explore the implications of InsP3 signaling in apicomplexan parasites for understanding early eukaryotic evolution.
- Identify potential therapeutic targets within apicomplexan InsP3 signaling pathways.
Main Methods:
- Genomic analysis to identify potential InsP3R homologs in apicomplexan species.
- Biochemical assays to study InsP3 production and its role in calcium signaling.
- Comparative analysis of PI signaling pathways across different eukaryotic lineages.
Main Results:
- Apicomplexan genomes lack canonical InsP3Rs despite evidence of InsP3 production.
- Evidence suggests apicomplexans may possess a primitive or non-canonical InsP3R.
- InsP3 signaling pathways in apicomplexans diverge from those in animal systems.
Conclusions:
- The absence of canonical InsP3Rs in apicomplexans points to unique signaling mechanisms.
- Understanding these non-canonical pathways can illuminate early eukaryotic signaling evolution.
- Targeting apicomplexan InsP3 signaling pathways presents a promising avenue for novel therapeutic interventions against parasitic infections.
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