Intramuscular fat （IMF） content in chickens significantly contributes to meat quality. The main objective of this study was to assess the expression of calcineudn （CAN） and Ca^2＋/calmodutin-dependent protein kina...Intramuscular fat （IMF） content in chickens significantly contributes to meat quality. The main objective of this study was to assess the expression of calcineudn （CAN） and Ca^2＋/calmodutin-dependent protein kinase （CAME） in lipogene- sis in chicken muscle. The chickens were slaughtered and sampled at the ages of 4, 8, and 16 weeks, respectively. IMF content and the expression of CaN subunits and CaMK isoforms were measured in thigh muscle tissue. The results showed that the IMF contents were higher in chickens at the age of 16 weeks compared with those in chickens at the ages of 4 and 8 weeks （P〈0.05）. The expression levels of fatty acid synthase （FAS） and fatty acid translocase CD36 （FAT/CD36） mRNA in 16-week-old chickens were all significantly up-regulated compared with those in 4-week-old chickens （P〈0.05）. The mRNA levels of CaNB and CaMK IV in 16-week-old chickens were significantly lower than those in 4-week-old chickens （P〈0.05）. But the CaMK II mRNA levels in 16-week-old chickens were significantly higher than those in 4-week-old chickens （P〈0.05）. To investigate the roles of CaMK and CaN in adipogenesis, SV cells were incubated in standard adipogenesis medium for 24 h and treated with specific inhibitor of CaMK and CaN. The ex- pressions of CCAAT/enhancer binding protein β（C/EBPJ3）, sterol regulatory element- binding protein 1 （SREBP1） and peroxisome proliferation-activated receptor ）, （PPARy） were dramatically enhanced by CsA and CaN inhibitor （P〈0.05）. KN93, a CaMK Ⅱ inhibitor, dramatically repressed the expression of those lipogenic genes （P〈0.05）. All the results above indicated that CaN and CaMK had different effects on adipogenesis in the muscle of chickens.展开更多
Growth is a polygenic trait that is under the influence of multiple physiological pathways regulating energy metabolism and muscle growth.Among the possible growth-regulating pathways in vertebrates,components of the ...Growth is a polygenic trait that is under the influence of multiple physiological pathways regulating energy metabolism and muscle growth.Among the possible growth-regulating pathways in vertebrates,components of the somatotropic axis are thought to have the greatest influence.There is growing body of literature focusing on the somatotropic axis and its role regulating growth in fish.This includes research into growth hormone,upstream hypothalamic hormones,insulin-like growth factors,and downstream signaling molecules.Many of these signals have both somatic effects stimulating the growth of tissues and metabolic effects that play a role in nutrient metabolism.Signals of other endocrine axes exhibit profound effects on the function of the somatotropic axis in vivo.In this review we highlight recent advances in our understanding of the teleost fish endocrine somatotropic axis,including emerging research using genetic modified models.These studies have revealed new aspects and challenges associated with regulation of the important steps of somatic growth.展开更多
基金Supported by Natural Science Foundation of Hubei Province of China(2011CDB012)Project of State Key Laboratory of Animal Nutrition(2004DA125184F1012)
文摘Intramuscular fat （IMF） content in chickens significantly contributes to meat quality. The main objective of this study was to assess the expression of calcineudn （CAN） and Ca^2＋/calmodutin-dependent protein kinase （CAME） in lipogene- sis in chicken muscle. The chickens were slaughtered and sampled at the ages of 4, 8, and 16 weeks, respectively. IMF content and the expression of CaN subunits and CaMK isoforms were measured in thigh muscle tissue. The results showed that the IMF contents were higher in chickens at the age of 16 weeks compared with those in chickens at the ages of 4 and 8 weeks （P〈0.05）. The expression levels of fatty acid synthase （FAS） and fatty acid translocase CD36 （FAT/CD36） mRNA in 16-week-old chickens were all significantly up-regulated compared with those in 4-week-old chickens （P〈0.05）. The mRNA levels of CaNB and CaMK IV in 16-week-old chickens were significantly lower than those in 4-week-old chickens （P〈0.05）. But the CaMK II mRNA levels in 16-week-old chickens were significantly higher than those in 4-week-old chickens （P〈0.05）. To investigate the roles of CaMK and CaN in adipogenesis, SV cells were incubated in standard adipogenesis medium for 24 h and treated with specific inhibitor of CaMK and CaN. The ex- pressions of CCAAT/enhancer binding protein β（C/EBPJ3）, sterol regulatory element- binding protein 1 （SREBP1） and peroxisome proliferation-activated receptor ）, （PPARy） were dramatically enhanced by CsA and CaN inhibitor （P〈0.05）. KN93, a CaMK Ⅱ inhibitor, dramatically repressed the expression of those lipogenic genes （P〈0.05）. All the results above indicated that CaN and CaMK had different effects on adipogenesis in the muscle of chickens.
基金supported by the National Basic Research Program of China(2010CB126302 and 2014CB138602)to Yin Zhan
文摘Growth is a polygenic trait that is under the influence of multiple physiological pathways regulating energy metabolism and muscle growth.Among the possible growth-regulating pathways in vertebrates,components of the somatotropic axis are thought to have the greatest influence.There is growing body of literature focusing on the somatotropic axis and its role regulating growth in fish.This includes research into growth hormone,upstream hypothalamic hormones,insulin-like growth factors,and downstream signaling molecules.Many of these signals have both somatic effects stimulating the growth of tissues and metabolic effects that play a role in nutrient metabolism.Signals of other endocrine axes exhibit profound effects on the function of the somatotropic axis in vivo.In this review we highlight recent advances in our understanding of the teleost fish endocrine somatotropic axis,including emerging research using genetic modified models.These studies have revealed new aspects and challenges associated with regulation of the important steps of somatic growth.
