<b>Bright and stable monomeric fluorescent protein derived from StayGold</b>

High brightness and photostability of StayGold make it a particularly attractive probe for long-term live cell imaging. However, its dimeric nature precludes its application as a fluorescent tag for some proteins. Here, we report the development and X-ray structures of a monomeric variant of StayGold (mBaoJin), which preserves the beneficial properties of its precursor while serving as a tag for structural proteins and membranes. We compare mBaoJin to other state-of-art GFPs and utilize it for super-resolution long-term live cell imaging and expansion microscopy.StayGold 具有极高的亮度与光稳定性，使其成为长期活细胞成像领域极具吸引力的荧光探针。然而，其天然二聚体特性限制了其作为部分蛋白质荧光标签的应用。本研究报道了StayGold的单体变体mBaoJin的开发工作及其X射线晶体结构解析；该变体保留了其前体的优良特性，同时可作为结构蛋白与膜结构的荧光标签。我们将mBaoJin与其他当前顶尖的绿色荧光蛋白 (GFP) 进行对比，并将其应用于超分辨率长期活细胞成像与扩展显微镜技术中。