AUTHOR=Huang Ying , Han Keke , Ren Qian 

TITLE=Cloning and Analysis of Gene Expression of Two Toll Receptors in Freshwater Pearl Mussel Hyriopsis cumingii

JOURNAL=Frontiers in Physiology

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2018.00133

DOI=10.3389/fphys.2018.00133

ISSN=1664-042X

ABSTRACT=<p>Toll receptors are involved in innate immunity of invertebrates. In this study, we identify and characterize two Toll genes (named <italic>HcToll4</italic> and <italic>HcToll5</italic>) from triangle sail mussel <italic>Hyriopsis cumingii. HcToll4</italic> has complete cDNA sequence of 3,162 bp and encodes a protein of 909 amino acids. <italic>HcToll5</italic> cDNA is 4,501 bp in length and encodes a protein of 924 amino acids. Both deduced HcToll4 and HcToll5 protein contain signal peptide, extracellular leucine rich repeats (LRRs), and intracellular Toll/interleukin-1 (IL-1) receptor domains. Quantitative real-time PCR analysis revealed that <italic>HcToll4</italic> and <italic>HcToll5</italic> were largely distributed in the hepatopancreas and could be detected in the gills and mantle. <italic>HcToll4</italic> and <italic>HcToll5</italic> expression could respond to <italic>Staphylococcus aureus, Vibrio parahaemolyticus</italic>, White spot syndrome virus (WSSV) or Poly I:C challenge. RNA interference by siRNA results showed that <italic>HcToll4</italic> and <italic>HcToll5</italic> were involved in the regulation of <italic>theromacin</italic> (<italic>HcThe</italic>) and <italic>whey acidic protein</italic> (<italic>HcWAP</italic>) expression. Based on these results, <italic>HcToll4</italic> and <italic>HcToll5</italic> might play pivotal function in <italic>H. cumingii</italic> innate immune response.</p>