Activated CIT phosphorylates MRLCs

Activated CIT phosphorylates MRLCs (mysoin regulatory light chains) at threonine T19 and serine S20 (also labeled in the literature as T18 and S19), and can restore stress fibre assembly when ROCKs are inhibited, although ROCKs play the dominant role in stress fiber formation-related phosphorylation of MRLCs. CIT-mediated phosphorylation of MRLCs may be important during cytokinesis. Unlike ROCKs, CIT does not phosphorylate the myosin binding subunit of the myosin phosphatase complex (Yamashiro et al. 2003).

激活的CIT（CIT激酶）在MRLCs（肌球蛋白调节轻链）的苏氨酸T19和丝氨酸S20位进行磷酸化（在文献中亦被标记为T18和S19），并在ROCKs（Rho激酶）被抑制时能够恢复应力纤维的组装，尽管ROCKs在MRLCs与应力纤维形成相关的磷酸化过程中发挥着主导作用。CIT介导的MRLCs磷酸化可能在细胞分裂过程中具有重要意义。与ROCKs不同，CIT不会磷酸化肌球蛋白磷酸酶复合物的肌球蛋白结合亚基（Yamashiro等，2003年）。