Lei Zhu, Yuanyuan Gao, Gaoliang Yuan, Xinyu Jiang, Jie Zhang, Xianliang Zhao, Chao Pei, Li Li, Xianghui Kong
Abstract
C1q domain-containing proteins (C1qDC) refer to a class of proteins, which contain the C1q domain. They play crucial roles in the immune response and recognition in different species, especially invertebrates and lower invertebrates. In this study, the full-length cDNA sequence of a novel C1qDC gene from Yellow River carp (Cyprinus carpio L.) (named as CcC1qDC) was identified and characterized. The results showed that the CcC1qDC was 958 bp in length, contains a 723 bp open reading frame (ORF) encoding a deduced protein of 241 amino acids with an estimated molecular weight of 27.2 kDa. The deduced amino acid sequence of CcC1qDC displayed a high identity to that of the common carp Cyprinus carpio (98.3%). The mRNA transcripts of CcC1qDC were ubiquitously expressed in different tissues of Yellow River carp, with a relatively high expression in the liver, gills, and spleen. The expression profile of CcC1qDC after LPS and poly I:C stimulations were also examined in Yellow River Carp by quantitative real-time PCR (qRT-PCR), and it was indicated that CcC1qDC expression levels were significantly up-regulated in the liver and spleen (p < 0.05), and down-regulated in kidney and head kidney (p < 0.05) after stimulations. Furthermore, rCcC1q showed an obvious bacterial agglutination activity against Aeromonas hydrophila and Bacillus subtilis, and the high binding activity to LPS and PGN in vitro. These results confirmed that CcC1qDC played an important role in immune recognition and response against pathogen infection in Yellow River Carp. This study could provide a theoretical basis for developing disease control strategies in aquaculture.
Keywords
Yellow River Carp, C1q domain-containing, Expression response, Pathogen recognition