SPECC1L is a cytoskeletal regulatory protein that plays critical roles in cell division, migration, and development. The protein binds directly to the myosin phosphatase complex MYPT1/PP1β and regulates its distribution between microtubules and filamentous actin networks, thereby controlling cytoskeletal dynamics during cell migration and division 1. SPECC1L functions downstream of IRF6 in palate development, where deficiency leads to oral epithelial adhesions and delayed palate elevation that can result in cleft palate 2. Disease-associated mutations cluster in the coiled-coil and calponin homology domains and severely impair microtubule association 2. Clinically, SPECC1L mutations cause facial clefting disorders and Teebi hypertelorism syndrome, with pathogenic variants specifically localized to two protein domains 3. The protein is also involved in oncogenic fusion events, with SPECC1L-NTRK fusions identified in pediatric cancers that respond to TRK inhibitor therapy 4, and BCL6-SPECC1L fusions found in nasopharyngeal carcinoma that disrupt BCL6's tumor suppressor function 5. These findings establish SPECC1L as a multifunctional cytoskeletal regulator essential for normal development and implicated in both congenital disorders and cancer.