Omics approaches applied to the study of the Myxozoan life cycle

• Grant number: 25/21127-6
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Start date: March 01, 2026
• End date: February 28, 2027
• Field of knowledge: Agronomical Sciences - Fishery Resources and Fishery Engineering - Inland Water Fishery Resources
• Principal Investigator: Edson Aparecido Adriano
• Grantee: Rayline Thaimenne Alves Figueredo
• Supervisor: Sonia Raquel Oliveira Rocha
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Institution abroad: Instituto De Ciências Biomédicas Abel Salazar, Portugal
• Associated to the scholarship: 23/06420-3 - Cnidarians of the Class Myxozoa parasitizing Rhaphiodon vulpinus: evolution, parasite-host interaction and nematocyst toxins, BP.DR

Abstract

Myxozoans are microscopic, spore-forming cnidarian endoparasites, widely distributed in marine and freshwater environments, with more than 3,000 species described, some of which have major economic impact, particularly in aquaculture, where they can cause disease outbreaks in farmed fish. Despite their relevance, knowledge of the molecular and regulatory aspects of the myxozoan life cycle remains limited. This project aims to investigate the life cycle of parasites of the class Myxozoa by applying integrated omics approaches to understand the molecular mechanisms regulating the alternation between the actinospore phase, in invertebrate hosts, and the myxospore phase, in vertebrate hosts. Recent advances in genomics have opened new perspectives for understanding the biology and evolution of these organisms. However, methodological challenges persist. The main barrier is contamination of parasite material with host DNA and RNA, which compromises the acquisition of pure and suitable samples for genomic and transcriptomic analyses. In this context, experimental maintenance of the life cycle under mesocosm conditions represents a viable alternative, enabling the control of infections and the collection of spores and other specific developmental stages. Among the promising approaches, epigenetics - particularly DNA methylation - stands out as a key regulatory mechanism of gene expression. Epigenetic processes may modulate gene activation or silencing according to the life cycle stage and host type, providing adaptive advantages against environmental and immunological pressures. As an experimental model, the life cycle of Ellipsomyxa mugilis, which infects the fish Chelon ramada (Mugilidae) and the polychaete Hediste diversicolor (Polychaeta), will be used. The cycle will be maintained in a mesocosm system at the Instituto de Ciências Biomédicas Abel Salazar (ICBAS), University of Porto, ensuring the production of spores in adequate quality and quantity. DNA will be sequenced using the Oxford Nanopore Technologies (ONT) platform, and RNA by Illumina, enabling genome and transcriptome characterization. Data integration will allow the identification of differentially expressed genes and their association with epigenetic profiles throughout the life cycle. Bioinformatic analyses will include genome assembly, functional annotation of genes, identification of metabolic pathways, and evaluation of epigenetic regulation in key processes such as development, cell differentiation, and immune evasion. The expected results include the generation of unprecedented genomic, transcriptomic, and epigenetic data for E. mugilis, advancing knowledge on molecular regulation in heteroxenous parasites.