Liganded Gq/11-activating GPCRs act as GEFs for Gq/11

G alpha q protein (or Gq/11) consists of four family members (G-alpha 11, -alpha 14, -alpha 15 and -alpha q). It activates phospholipase C (PLC) (Dowal L et al, 2006). PLC hydrolyzes phosphatidylinositol (PIP2) to diacyl glycerol (DAG) and inositol triphosphate (IP3). DAG acts as a second messenger that activates protein kinase C (PKC) and IP3 can bind to IP3 receptors, particular calcium channels in the endoplasmic reticulum (ER). Calcium flow causes the cytosolic concentration of calcium to increase, causing a cascade of intracellular changes and activity.

Gαq蛋白（或称Gq/11）由四个家族成员组成，包括G-α11、G-α14、G-α15和G-αq。该蛋白能够激活磷脂酶C（PLC）（Dowal L 等人，2006年）。PLC催化磷脂酰肌醇（PIP2）水解生成二酰甘油（DAG）和肌醇三磷酸（IP3）。DAG作为一种第二信使，激活蛋白激酶C（PKC），而IP3能够与IP3受体结合，尤其是内质网（ER）中的钙通道。钙流的增加导致细胞质中钙浓度升高，引发一系列细胞内变化和活动。