Identification of differentially expressed genes in hypothalamus of chicken during cold stress

Abstract

In order to discover the mechanism of cold stress and identify differentially expressed genes in hypothalamus during cold stress, 4 weeks of age Huainan partridge chickens, Chinese indigenous breed, were chosen for 24 h cold stress and then hypothalamus were isolated and labeled by reverse transcription reaction for cDNA. Labeled cDNA were hybridized with cDNA microarray. After scanning and image processing, the different gene expression profiling of hypothalamus and normal control was investigated. The differentially expressed genes included 334 down-regulated genes and 543 up-regulated genes. In these differentially regulated genes, myosin heavy chain polypeptide 11 (MYH11), light chain polypeptide 9 (MYL9) and tenascin-Y (TNXB), etc., which involved in muscle activity were significantly down-regulated. Genes like cholecystokinin (CCK), neuropeptide Y (NPY), neuropeptide Y receptor 5 (NPY5R), hypocretin receptor 2 (HCRTR2) and hypocretin neuropeptide precursor (HCRT) which responsible for regulation of feeding behavior were significantly up-regulated. In addition, genes responsible for lipid synthesis, like apolipoprotein (APOB) and agouti related protein homolog (AGRP), were also up-regulated. Through pathway analysis using the Kyoto Encyclopedia of Gene and Genomics, during 24 h cold stress, the neuroactive ligand-receptor interaction was firstly initiated in chickens for stimulation of central nervus for feed intake. Adipocytokine signaling pathway was in high activation for supplementation of body energy. Jak-STAT, Ca(2+) signaling pathway and other biological reactions were also initiated in response to cold stress. The biological pathways participated in cold stress would provide important information for clarify the mechanism of cold stress and the differentially expressed genes would give much help for screening of candidate genes in breeding of cold stress resistant lines.

Chronic Mild Cold Conditioning Modulates the Expression of Hypothalamic Neuropeptide and Intermediary Metabolic-Related Genes and Improves Growth Performances in Young Chicks

“…Low and high environmental temperatures are the most challenging stressors impacting both poultry and livestock industries. Cold stress, for instance, has been reported to cause an estimated total annual economic loss to the Chinese poultry industry of 100 million in currency [ 5 ]. A tremendous amount of seminal work has been done to identify the animal physiological and behavioral responses to cold stress and improve management strategies, however, the underlying molecular mechanisms are still not completely defined.…”

“…These neuropeptides interact in a complex way with each other and with the central melanocortin system, melanin-concentrating hormone, orexin, ghrelin and adiponectin, to mention a few, to regulate energy homeostasis in mammals [for review see [ 47 ]]. A recent study, using microarray analysis, reported 24h-cold exposure-induced changes in chicken hypothalamic gene expression [ 5 ]. Our work complements and adds to this study by showing that CMCC down regulated the expression of the potent orexigenic NPY and anorexigenic CART genes which may explain the similar feed intake observed between the control and CMCC chicks.…”

“…In expanding worldwide broiler (meat-type chicken) production, the effects of cold stress on growth performances are controversial depending on the stress severity, the exposure period, and the age of the chicken. Indeed, sudden severe decrease of environmental temperature has been reported to negatively affect growth performance (feed efficiency, meat yield, ascites, mortality) [ 4 ] and result in serious annual economic losses to the livestock and poultry industries [ 5 ]. On the other hand, conditioning exposure of chickens at an early age to moderate decreased environmental temperature has been reported to have a long-lasting effect and improve the ability of the chicken to acclimatize and to cope better with stressors in later life [ 6 ].…”

“…We also showed that acute cold stress alters the expression of key genes (leptin and uncoupling protein, UCP) involved in the regulation of energy intake and expenditure in 5 week old broiler chickens. Several recent studies investigating the effect of acute or chronic severe cold exposure (-15 to 12°C) on neuropeptides, antioxidant, immune, immunoglobulin and cytokine systems in immune organs, heart, hypothalamus and gastrointestinal tract in old (15 days to 4 weeks) chickens have been reported [ 5 , 19 – 24 ]. However, data related to the effect of chronic mild cold conditioning (CMCC) on metabolic-related genes in young chicks are scarce.…”

Identification of the acclimation genes in transcriptomic responses to heat stress of White Pekin duck

“…In the current study, several meaningful KEGG pathways that are associated with energy homeostasis and lipid metabolism were significantly enriched, such as adipocytokine signaling, cAMP signaling, and fatty acid biosynthesis. Interestingly, the neuroactive ligandreceptor interaction is initiated in chickens to stimulate the central nervous system for feed intake under cold stress conditions (Chen et al 2014). From the significant KEGG pathways, we inferred that the adaptable genes induced the energy homeostasis to respond to the relatively high energy demand under heat stress conditions.…”