MDM2 and myeloproliferative disorder: In addition, Nakatake et al. (2012) showed that the JAK2V617F mutation affects the p53 response to DNA damage through the accumulation of Murine double minute 2 (MDM2), an E3 ubiquitin ligase that binds to p53 and promotes its proteosomal degradation in myeloproliferative neoplasms.