The effect of feeding with different protein levels on internal organ weight and gene expression of MEF2A and ATF3 in crossbred local chicken using RT-PCR

BACKGROUND: Myogenic enhancer transcription factor 2A (MEF2A) is a transcription factor known for its role in controlling skeletal muscle regeneration and metabolic processes, while activating transcription factor 3 (ATF3) is a stress-induced transcription factor that plays a role in modulating metabolic processes, immunity, and oncogenesis. Environmental factors, such as dietary protein, can influence gene expression levels. Insufficient protein intake can negatively affect the metabolic performance of internal organs, leading to the abnormal weight of internal organs. A total of 192 non-sexing crossbred local chickens day-old-chick (DOC) with a completely randomized design (CRD) method of 3 treatments and 8 replicates. Real-time polymerase chain reaction (RT-PCR) is used to measure the gene expression levels. This study aimed to determine the effect of feeding with various protein levels on internal organ weight and gene expression of MEF2A and ATF3 in crossbred local chickens. RESULT: The analysis of treatment revealed that the results were not significantly different (P > 0.05) on gizzard weight and spleen weight. However, it shows a significantly different result (P < 0.05) on heart weight and a highly significantly different result (P < 0.01) on pancreas weight. These findings suggest that protein levels in the diet had a significant impact on heart and pancreas weights. In terms of gene expression, the increased utilization of protein did not result in an elevation of MEF2A gene expression in both muscle tissue and liver tissue. Specifically, in muscle tissue, MEF2A gene expression was highly expressed at 18% protein feed for the starter phase and 16% for the finisher phase. Conversely, in liver tissue, MEF2A gene expression was highly expressed at 22% protein feed for the starter phase and 20% for the finisher phase. Moreover, ATF3 gene expression in muscle tissue exhibited a negative correlation with increasing feed protein levels. CONCLUSION: The results indicate that varying protein levels did not lead to abnormal weights in the liver, kidney, heart, and spleen organs. Additionally, the differential gene expression patterns of MEF2A and ATF3 in muscle tissue and liver tissue suggest that these genes respond differently to varying protein-feeding treatments. These findings provide insights into the complex regulatory mechanisms of MEF2A and ATF3 genes in relation to protein levels and organ-specific responses in crossbred local chickens.