YAP, an important coactivator of the Hippo pathway, regulates the transcription of targeted genes including CTGF, and is closely associated with the development of CKD.[46, 47, 48, 49] Two critical domains that regulate the activity of YAP are WW1 and WW2.[50, 51] Our work showed that 254–388 amino acid region of NEU4 was directly bound to the WW2 domain located at 231–263 region. The gene discussed is CCN2; the disease is chronic kidney disease.