CRISPR-Cas9 基因编辑示意图

生成一张 4:5 竖版「CRISPR-Cas9 基因编辑示意图」案例图，所属分类为「科研与学术图」。白色背景四步骤 CRISPR-Cas9 示意图，呈现导向 RNA 结合、DNA 靶向、双链切割及两条修复通路，风格简洁符合期刊规范。画面需要完整呈现上述主体、构图、配色、材质、光线和整体风格；可见文字以自然简体中文为主，必要的技术缩写、代码、变量名、学术符号、单位、拉丁物种名或装饰性外文可保留。

A clean, Nature-journal-quality vector illustration explaining the steps of CRISPR-Cas9 gene editing. The figure is composed as a vertical sequential diagram on a white background with a subtle grid. Four numbered panels flow top to bottom. Panel 1 shows the Cas9 protein complex with the guide RNA strand in a soft teal colour, labelled "guide RNA" and "Cas9 nuclease". Panel 2 depicts the guide RNA hybridising to the target double-stranded DNA helix, with a dashed alignment arrow and the label "target sequence". Panel 3 shows the moment of cleavage — a red dashed line bisecting both DNA strands at the cut site, labelled "double-strand break". Panel 4 illustrates two repair pathways forking left and right: NHEJ (showing a small insertion/deletion, labelled "NHEJ — gene disruption") and HDR (showing a new sequence inserted from a template strand, labelled "HDR — precise edit"). Colours use a restrained four-tone palette: off-white background, slate-blue DNA, teal RNA, coral red cut markers, and warm-grey labels in a clean sans-serif typeface. All label text is in English. Thin hairline rules separate panels. The overall feel is a publication-ready figure from a peer-reviewed molecular biology journal, precise and uncluttered.