PUBLICATION

Transcriptome analysis revealed positive selection of immune-related genes in tilapia

Authors
Xiao, J., Zhong, H., Liu, Z., Yu, F., Luo, Y., Gan, X., Zhou, Y.
ID
ZDB-PUB-150211-29
Date
2015
Source
Fish & shellfish immunology   44(1): 60-5 (Journal)
Registered Authors
Zhou, Yi
Keywords
Blue tilapia, Divergence time, Evaluation, High-throughput sequencing, Immune genes, Positive selection
MeSH Terms
  • Animals
  • Cichlids/genetics*
  • Cichlids/metabolism
  • Evolution, Molecular*
  • Female
  • Fish Proteins/genetics*
  • Fish Proteins/metabolism
  • Male
  • Selection, Genetic*
  • Transcriptome*
PubMed
25659230 Full text @ Fish Shellfish Immunol.
Abstract
High-throughput sequencing of transcriptome promises a new approach for detecting evolutionary divergence among species. Up to now, the information about evolution of immune genes in cultured fish, especially in tilapias which would aid to understand the molecular basis of immune phenotypic differentiation in these aquaculture species is still lack. Thus, in the present study, we used high-throughput sequencing to obtain large amount of gene sequences in tilapia and characterized the diversity of orthologs among Nile tilapia, blue tilapia and zebrafish. A total of 52,424,506 raw reads, representing 31,404 unigenes were obtained from blue tilapia cDNA library of mixed tissues, including brain, pituitary, gill, heart, liver, spleen, kidney, intestine, muscle, testis and ovary. Based on Ks value, we calculated that the divergence time between Nile tilapia and blue tilapia is 2.93 million years ago. And the tilapias are both apart from zebrafish in 197 million years ago. Furthermore, the positive selected genes were identified by calculating of Ka/Ks ratio. Several immune-related genes were identified as positively selected genes, such as Notch2 and nfatc3b. Considering that these genes play a crucial role in immune regulating function, the immune system genes met a great variation under environment selection in tilapias which suggests fast evolution in immune system of cultured tilapias.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping