Identification of immune genes of the miiuy croaker (Miichthys miiuy) by sequencing and bioinformatic analysis of ESTs

Miiuy croaker (Miichthys miiuy) is an economically important fish in China. However, genomic research on this species is still in its infancy, and genomic resources are largely unavailable. In order to isolate functional genes involved in immunity, a normalized cDNA library was constructed from the spleen of the miiuy croaker. A total of 5053 ESTs from the library were sequenced and compared with sequences in the GenBank database. The 4609 high-quality ESTs were assembled into 3221 unigenes. Based on sequence similarities, 193 immune genes were identified such as major histocompatibility complex, cytokines and cytokine receptors, adhesive proteins, stress proteins, transcription factors for immune response, immunoglobulin and coagulation factors. Our study thus provides both a detailed annotation of immune genes in miiuy croaker and a collection of novel transcripts of Fc receptor-like 5 in teleost for the first time.