第7章 细胞通讯与信号转导.ppt

肌醇磷酸通路 ? 双信号系统途径 ： 胞外信号因子 → G蛋白偶连受体→ G蛋白→ 磷酸脂酶C (PLC) →IP3→ [Ca2+]? → CaM →细胞应答 → → DAG → 活化PKC → 不同靶蛋白 Table 7-5 Summary of cellular responses elicited by adding IP3 to either permeabilized or intact cells. CELL TYPE RESPONSE Vascular smooth muscle contraction Stomach smooth muscle contraction Skeletal muscle contraction Slime mold Cyclic GMP formation, actin polymerization Blood platelets Shape change, aggregation Salamander rods Modulation of light response Xenopus oocytes Calcium mobilization, membrane depolarization Sea urchin eggs Membrane depolarization, cortical reaction Lacrimal gland Increased potassium current Table 7-6: Examples of responses mediated by protein kinase C TISSUE RESPONSE Blood platelets Serotonin release Mast cells Histamine relase Adrenal medulla Secretion of epinephrine Pancreas Secretion of insulin Pituitary cells Secretion of calcitonin Thyroid Secretion of synthesis Testes Testosterone synthesis Neurons Dopamine release 7.4.3 受体酪氨酸激酶和RTK-Ras 蛋白信号通路 ?受体酪氨酸激酶(RTKs) 包括 6个亚家族 ?信号转导：配体(ligand) →受体(receptor)→受体二聚体(receptor dimers) →受体相互磷酸化(receptors to phosphorylate each other) → 活化 RTK → 信号转导 ? RTK- Ras 信号通路 7.4.4 细胞表面其它酶联受体 ?受体丝氨酸/苏氨酸激酶(receptor serine/threonine kinases) ?受体酪氨酸磷酸酯酶(receptor tyrosine phosphatases) ?受体鸟苷酸环化酶(receptor guanylate cyclase) ?酪氨酸蛋白激偶联系的受体(tyrosine kinase-linked receptors) 两个家族： Src: 蛋白受体家族 (protein receptor family) Janus: 激酶家族受体 (kinase family receptor) STAT(信号转导子和转录激活子)和 JAK-STAT 通路 Cytokines (细胞因子): 直接控制基因表达 Figure 7-17 TGF-β receptors activate gene regulatory proteins directly at the plasma membrane. 7.4.6 植物中的细胞通讯 植物激素 乙烯信号途径 光受体途径 Figure 7-23 Structure of plant hormones A current view of the ethylene two-component signaling pathway. (A) In the absence of ethylene, the receptors and the MAP-kinase module are active, leading to inhibition of the gene regulatory proteins in the nucleus that are responsible for the transcription of