Selection for growth rate and body size have altered the expression profiles of somatotropic axis genes in chickens

PLoS One. 2018 Apr 9;13(4):e0195378. doi: 10.1371/journal.pone.0195378. eCollection 2018.

Abstract

The growth hormone / insulin-like growth factor-1 (GH/IGF-1) pathway of the somatotropic axis is the major controller for growth rate and body size in vertebrates, but the effect of selection on the expression of GH/IGF-1 somatotropic axis genes and their association with body size and growth performance in farm animals is not fully understood. We analyzed a time series of expression profiles of GH/IGF-1 somatotropic axis genes in two chicken breeds, the Daweishan mini chickens and Wuding chickens, and the commercial Avian broilers hybrid exhibiting markedly different body sizes and growth rates. We found that growth rate and feed conversion efficiency in Daweishan mini chickens were significantly lower than those in Wuding chickens and Avian broilers. The Wuding and Daweishan mini chickens showed higher levels of plasma GH, pituitary GH mRNA but lower levels of hepatic growth hormone receptor (GHR) mRNA than in Avian broilers. Daweishan mini chickens showed significantly lower levels of plasma IGF-1, thigh muscle and hepatic IGF-1 mRNA than did Avian broilers and Wuding chickens. These results suggest that the GH part of the somatotropic axis is the main regulator of growth rate, while IGF-1 may regulate both growth rate and body weight. Selection for growth performance and body size have altered the expression profiles of somatotropic axis genes in a breed-, age-, and tissue-specific manner, and manner, and alteration of regulatory mechanisms of these genes might play an important role in the developmental characteristics of chickens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Avian Proteins / blood
  • Avian Proteins / genetics
  • Body Size / genetics
  • Body Weight / genetics
  • Breeding
  • Carrier Proteins / blood
  • Carrier Proteins / genetics
  • Chickens / genetics*
  • Chickens / growth & development*
  • Chickens / metabolism
  • Gene Expression Regulation, Developmental
  • Growth Hormone / blood
  • Growth Hormone / genetics
  • Insulin-Like Growth Factor Binding Protein 2 / blood
  • Insulin-Like Growth Factor Binding Protein 2 / genetics
  • Insulin-Like Growth Factor I / genetics
  • Insulin-Like Growth Factor I / metabolism
  • Liver / metabolism
  • Muscle, Skeletal / metabolism
  • Pituitary Gland / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Receptor, IGF Type 1 / genetics
  • Receptors, Somatotropin / genetics
  • Species Specificity
  • Transcriptome

Substances

  • Avian Proteins
  • Carrier Proteins
  • Insulin-Like Growth Factor Binding Protein 2
  • RNA, Messenger
  • Receptors, Somatotropin
  • Insulin-Like Growth Factor I
  • Growth Hormone
  • Receptor, IGF Type 1
  • somatotropin-binding protein

Grants and funding

This work was partially funded by National Natural Science Foundation of China (31260532, 31560618, 31572359) (JJ), Yunnan Provincial Natural Science Foundation (2011FA015, 2016FA046) (JJ), and National Science and Technology Program in the 13th Five-Year Plan (2015BAD03B03-4) (CG). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.