Tibetan chicken, an indigenous breed, is highly adapted to the extreme environment of the Qinghai–Tibet Plateau. It serves as a model organism to identify genetic differences between hypoxia-adapted and lowland breeds. However, the mechanisms underlying hypoxia adaptation are yet unclear. This study aimed to identify differently abundant proteins (DAPs) and elucidate the mechanisms involved in hypoxic adaptation in the Tibetan chicken. In this study, we obtained proteome data for the embryonic heart tissues of Tibetan and Chahua chickens incubated under hypoxia (TCH and CHH) and normoxia (TCN and CHN) using isobaric tags for relative and absolute quantitation (iTRAQ) technology. We identified 4210 proteins from 53,352 unique peptides in the heart tissue of chicken embryos. Pairwise TCH vs. CHH, TCH vs. TCN, CHH vs. CHN, and TCN vs. CHN comparisons revealed 118, 176, 103, and 162 differently abundant proteins, respectively. Several key proteins (EGLN1, MAP2K2, MYLK, QARS, NOTCH2, and MYH7) and pathways (glutathione metabolism, PPAR signaling pathway, and vascular smooth muscle contraction) were identified and considered important candidates for high-altitude adaptation in Tibetan chicken. This study provides novel insights into the chicken embryonic heart tissue and furthers the current understanding of the mechanisms of survival among animals in high-altitude environments.

藏族鸡是土生土长的品种，高度适应了青藏高原的极端环境。它可以作为模型生物来识别低氧适应品种和低地品种之间的遗传差异。然而，低氧适应的潜在机制尚不清楚。这项研究旨在鉴定不同的丰富蛋白质（DAP），并阐明藏鸡肉中低氧适应的机制。在这项研究中，我们使用等压标记用于相对和绝对定量（iTRAQ）技术，获得了在低氧（TCH和CHH）和常氧（TCN和CHN）下孵育的藏族和茶花鸡胚胎心脏组织的蛋白质组数据。我们从鸡胚心脏组织的53,352种独特肽中鉴定出4210种蛋白质。成对的TCH与CHH，TCH与TCN，CHH与CHN以及TCN与。CHN比较显示分别有118、176、103和162种不同的丰富蛋白质。确定了几个关键蛋白（EGLN1，MAP2K2，MYLK，QARS，NOTCH2和MYH7）和途径（谷胱甘肽代谢，PPAR信号传导途径和血管平滑肌收缩），并被认为是藏鸡高海拔适应性的重要候选者。这项研究提供了对鸡胚胎心脏组织的新颖见解，并进一步了解了目前在高海拔环境中动物之间的生存机制。血管平滑肌收缩和血管平滑肌收缩）被认为是藏鸡肉高海拔适应的重要候选者。这项研究提供了对鸡胚胎心脏组织的新颖见解，并进一步了解了目前在高海拔环境中动物之间的生存机制。血管平滑肌收缩和血管平滑肌收缩）被认为是藏鸡肉高海拔适应的重要候选者。这项研究提供了对鸡胚胎心脏组织的新颖见解，并进一步了解了目前在高海拔环境中动物之间的生存机制。