Whitehead Institute for Biomedical Research, Cambridge, MA 02142.
Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142.
Mol Biol Cell. 2022 Oct 1;33(12):ar110. doi: 10.1091/mbc.E22-03-0091. Epub 2022 Aug 3.
Prior work has identified signal sequences and motifs that are necessary and sufficient to target proteins to specific subcellular regions and organelles such as the plasma membrane, nucleus, endoplasmic reticulum, and mitochondria. In contrast, minimal sequence motifs that are sufficient for Golgi localization remain largely elusive. In this work, we identified a 37-amino acid alternative open reading frame (altORF) within the mRNA of the centromere protein CENP-R. This altORF peptide localizes specifically to the cytoplasmic surface of the Golgi apparatus. Through mutational analysis, we identify a minimal 10-amino acid sequence and a critical cysteine residue that are necessary and sufficient for Golgi localization. Pharmacological perturbations suggest that this peptide undergoes lipid modification to promote its localization. Together, our work defines a minimal sequence that is sufficient for Golgi targeting and provide a valuable Golgi marker for live cell imaging.
先前的工作已经确定了信号序列和基序，这些序列和基序对于将蛋白质靶向到特定的亚细胞区域和细胞器（如质膜、核、内质网和线粒体）是必要且充分的。相比之下，对于高尔基体定位而言，足够的最小序列基序仍然很大程度上难以捉摸。在这项工作中，我们在着丝粒蛋白 CENP-R 的 mRNA 中鉴定出一个 37 个氨基酸的替代开放阅读框 (altORF)。这个 altORF 肽特异性定位于高尔基体的细胞质表面。通过突变分析，我们确定了一个最小的 10 个氨基酸序列和一个关键的半胱氨酸残基，它们对于高尔基体的定位是必要且充分的。药理学干扰表明，这种肽经历了脂质修饰以促进其定位。总之，我们的工作定义了一个足以用于高尔基体靶向的最小序列，并为活细胞成像提供了一个有价值的高尔基体标记物。
