关键词: 绵羊(Ovis aries), 胚胎背最长肌, 蛋白质组学, 生物信息学分析

Abstract:

【Objective】Sheep is an important economic livestock and its skeletal muscle growth and development have a deep bond with meat production traits. The sheep embryonic period is an essential stage for skeletal muscle growth, analyzing and mining the proteome data of sheep embryonic skeletal muscle in this period has a great significance to reveal the muscle development process and screen their key regulation proteins.【Method】The longissimus dorsi of Chinese merino sheep at embryonic age of 85 days, 105 days and 135 days were selected for protein qualification by using tandem mass tag (TMT) and 1316 differential abundance proteins were obtained finally. GO, KEGG and R bioinformatic methods were used to cluster, annotate and analyze the differential abundance proteins. And the candidate proteins were testified by using bioinformatic methods.【Result】Based on the previous results, the cluster analysis on differential abundance proteins illustrated that the cluster 5 proteins were significantly expressed on embryonic age of 105 days with high abundance. GO and KEGG analysis on cluster 5 proteins showed these proteins were significantly involved in protein metabolism biology process and notably enriched in PI3K-AKT signal pathway in which RAC-beta serine/threonine-protein kinase isoform X1(ATK2) has a high abundance. Meanwhile, the results of bioinformatics showed that the AKT2 was composed of 481 amino acids and the theoretical molecular weight was 55.58kD. It consists of 66 positively charged amino acid residues and 72 negatively charged amino acid residues, the theoretical isoelectric point was 6.08, the hydrophilicaverage coefficient was -0.454, 12 N-terminal glycosylation sites and 71 phosphorylation sites were found in AKT2. The homology of AKT2 and protein kinase-like (PK-like) was 99% and it belongs to the family of protein kinases catalytic subunit.【Conclusion】The proteome data analysis of sheep embryonic skeletal muscle showed that embryonic age of 105 days is a key point of sheep embryonic skeletal fiber cell from proliferation and differentiation to hypertrophy. The PI3K-AKT signaling pathway which has function of regulating growth and development of embryonic skeletal muscle fibers was significantly enriched, and ATK2 is a key candidate regulation protein in this pathway. To summarize, the study has a theoretical guiding significance to reveal the growth and development and its molecular regulation mechanism of embryonic skeletal muscle.

Key words: sheep (Ovis aries), embryonic longissimus dorsi, proteomic, bioinformatics analysis