The ferritin gene in ridgetail white prawn Exopalaemon carinicauda: cloning, expression and function

Area of Science:

• Marine Biology
• Molecular Biology
• Biochemistry

Background:

• Ferritin is a key protein for iron storage and homeostasis in animals.
• Understanding ferritin's role in crustaceans is essential for aquatic animal health and aquaculture.

Purpose of the Study:

• To characterize the ferritin cDNA (EcFer) from Exopalaemon carinicauda.
• To investigate the expression patterns of EcFer during different developmental stages and in response to heavy metal stress.
• To confirm the iron-binding capacity of the recombinant EcFer protein.

Main Methods:

• Cloning and sequencing of the EcFer cDNA.
• Quantitative real-time PCR (qRT-PCR) for gene expression analysis.
• Heterologous expression of EcFer in Pichia pastoris and protein purification.
• Iron uptake assays using purified recombinant EcFer.

Main Results:

• A 516 bp EcFer cDNA encoding a 171 amino acid protein was identified, featuring an iron-responsive element (IRE) in its 5'-UTR.
• EcFer mRNA was predominantly expressed in the hepatopancreas.
• EcFer expression significantly increased following exposure to CuSO4 and CdCl2.
• EcFer transcript levels were low in early developmental stages (gastrula, zoea) but increased from the egg protozoea stage onwards.
• Recombinant EcFer expressed in Pichia pastoris demonstrated iron-uptake capability.

Conclusions:

• EcFer plays a significant role in iron metabolism and homeostasis in Exopalaemon carinicauda.
• EcFer expression is regulated by both developmental cues and environmental stressors like heavy metals.
• The characterized EcFer protein is functional and capable of binding iron, supporting its role in iron storage.