{
  "style": "basic",
  "protein_icon": "generic-protein-capsule",
  "scope": "Illustrative teaching models. Node names, timings and causal rules are specified examples, not experimental results.",
  "visual_references": [
    {
      "url": "https://www.biorender.com/template/blank-pathway-linear",
      "inspection": "Public lightbox visually inspected for capsule nodes, Y/U receptors, arrows and compartment layout."
    },
    {
      "url": "https://www.biorender.com/template/intracellular-layout-receptor-signaling-from-plasma-membrane-to-nucleus-2",
      "inspection": "Public lightbox visually inspected for capsule complexes, separate P badges and nuclear import. Original SVG composition; no source art copied."
    }
  ],
  "examples": [
    {
      "id": "cascade",
      "title": "Y 型受体：磷酸化级联",
      "question": "受体二聚后，信号怎样逐级传给下游蛋白？",
      "receptors": [
        {
          "kind": "y",
          "x": 250
        }
      ],
      "proteins": [
        {
          "id": "A",
          "x": 250,
          "y": 325,
          "time": 6
        },
        {
          "id": "B",
          "x": 500,
          "y": 325,
          "time": 10
        },
        {
          "id": "C",
          "x": 750,
          "y": 455,
          "time": 14
        }
      ],
      "edges": [
        {
          "d": "M250 251V292",
          "time": 5
        },
        {
          "d": "M310 325H440",
          "time": 9
        },
        {
          "d": "M560 325H750V422",
          "time": 13
        }
      ],
      "duration": 18,
      "steps": [
        [
          0,
          "配体结合"
        ],
        [
          2,
          "Y 型单体靠近并组成二聚体"
        ],
        [
          4,
          "受体胞内尾部磷酸化"
        ],
        [
          6,
          "蛋白 A 磷酸化"
        ],
        [
          10,
          "A → B"
        ],
        [
          14,
          "B → C"
        ]
      ]
    },
    {
      "id": "import",
      "title": "U 型受体：复合物入核与 RNA 生成",
      "question": "活化后的蛋白怎样组装、入核并启动转录？",
      "receptors": [
        {
          "kind": "u",
          "x": 250
        }
      ],
      "proteins": [
        {
          "id": "A",
          "x": 220,
          "y": 325,
          "time": 6
        },
        {
          "id": "B",
          "x": 410,
          "y": 325,
          "time": 6
        }
      ],
      "edges": [
        {
          "d": "M250 251V275H220V292",
          "time": 5
        },
        {
          "d": "M250 275H410V292",
          "time": 5
        },
        {
          "d": "M220 358V440H365",
          "time": 8
        },
        {
          "d": "M410 358V386",
          "time": 8
        },
        {
          "d": "M510 440H650",
          "time": 12
        },
        {
          "d": "M750 492V514",
          "time": 16
        },
        {
          "d": "M870 512V423",
          "time": 17
        }
      ],
      "duration": 20,
      "steps": [
        [
          0,
          "配体结合"
        ],
        [
          2,
          "U 型单体组成二聚体"
        ],
        [
          4,
          "受体尾部磷酸化"
        ],
        [
          6,
          "A 与 B 磷酸化"
        ],
        [
          8,
          "A/B 复合物形成"
        ],
        [
          12,
          "复合物向核膜移动"
        ],
        [
          14,
          "复合物通过核膜开口"
        ],
        [
          17,
          "靶基因产生 RNA"
        ]
      ]
    },
    {
      "id": "convergence",
      "title": "Y/U 两路输入：汇合与阻断",
      "question": "阻断左路 A 后，右路 B 能否继续传递信号？",
      "receptors": [
        {
          "kind": "y",
          "x": 270
        },
        {
          "kind": "u",
          "x": 730
        }
      ],
      "proteins": [
        {
          "id": "A",
          "x": 270,
          "y": 330,
          "time": 6
        },
        {
          "id": "B",
          "x": 730,
          "y": 330,
          "time": 8
        },
        {
          "id": "C",
          "x": 500,
          "y": 495,
          "time": 13
        }
      ],
      "edges": [
        {
          "d": "M270 251V297",
          "time": 5
        },
        {
          "d": "M730 251V297",
          "time": 7
        },
        {
          "d": "M270 363V420H465V463",
          "time": 12,
          "branch": "A"
        },
        {
          "d": "M730 363V420H535V463",
          "time": 12,
          "branch": "B"
        }
      ],
      "duration": 18,
      "steps": [
        [
          0,
          "两类配体分别结合 Y/U 型受体"
        ],
        [
          2,
          "两路受体分别二聚"
        ],
        [
          4,
          "两路受体尾部磷酸化"
        ],
        [
          6,
          "左路 A 磷酸化"
        ],
        [
          8,
          "右路 B 磷酸化"
        ],
        [
          13,
          "任一路可维持 C 的磷酸化"
        ]
      ]
    }
  ]
}