Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA.
Division of Biological Systems and Engineering, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Division of Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
Cell Rep. 2023 Nov 28;42(11):113311. doi: 10.1016/j.celrep.2023.113311. Epub 2023 Oct 26.
Short polypeptides encoded by small open reading frames (smORFs) are ubiquitously found in eukaryotic genomes and are important regulators of physiology, development, and mitochondrial processes. Here, we focus on a subset of 298 smORFs that are evolutionarily conserved between Drosophila melanogaster and humans. Many of these smORFs are conserved broadly in the bilaterian lineage, and ∼182 are conserved in plants. We observe remarkably heterogeneous spatial and temporal expression patterns of smORF transcripts-indicating wide-spread tissue-specific and stage-specific mitochondrial architectures. In addition, an analysis of annotated functional domains reveals a predicted enrichment of smORF polypeptides localizing to mitochondria. We conduct an embryonic ribosome profiling experiment and find support for translation of 137 of these smORFs during embryogenesis. We further embark on functional characterization using CRISPR knockout/activation, RNAi knockdown, and cDNA overexpression, revealing diverse phenotypes. This study underscores the importance of identifying smORF function in disease and phenotypic diversity.
短肽由小开放阅读框（smORFs）编码，广泛存在于真核生物基因组中，是生理、发育和线粒体过程的重要调节剂。在这里，我们专注于在黑腹果蝇和人类之间进化上保守的 298 个 smORFs 亚组。这些 smORFs 中有许多在两侧对称动物谱系中广泛保守，约 182 个在植物中保守。我们观察到 smORF 转录物的空间和时间表达模式非常不均匀——表明广泛存在组织特异性和阶段特异性的线粒体结构。此外，对注释功能域的分析表明，smORF 多肽预测富集定位于线粒体。我们进行了胚胎核糖体谱分析实验，发现 137 个这些 smORFs 在胚胎发生过程中被翻译。我们进一步通过 CRISPR 敲除/激活、RNAi 敲低和 cDNA 过表达进行功能表征，揭示了多种表型。这项研究强调了识别 smORF 在疾病和表型多样性中的功能的重要性。
