 He subsequently gradually rose in ranks.After Gao Huan's death in 547, Yang continued to serve Gao Huan's heir Gao Cheng, who took over as regent.In 549, Gao Cheng convened a meeting with Yang, Chen Yuankang, and Cui Jishu to discuss the process of seizing the throne from Emperor Xiaojing of Eastern Wei, when Gao Cheng's slave Lan Jing made a surprise attack on Gao Cheng, killing him and Chen.