Trichinella spiralis inhibits myoblast differentiation by targeting SQSTM1/p62 with a secreted E3 ubiquitin ligase

Trichinella spiralis infection is associated with the formation of cysts within host skeletal muscle cells, thereby enabling immune evasion and subsequent growth and development; however, the pathogenic factors involved in this process and their mechanisms remain elusive. Here, we found that Ts-RNF secreted by T. spiralis is required for its growth and development in host cells. Further study revealed that Ts-RNF functions as an E3 ubiquitin ligase that targets the UBA domain of SQSTM1/p62 by forming K63-type ubiquitin chains. This modification interferes with autophagic flux, leading to impaired mitochondrial clearance and abnormal myotube differentiation and fusion. Our results established that T. spiralis increases its escape by interfering with host autophagy via the secretion of an E3 ubiquitin ligase. [Display omitted] •Trichinella spiralis-secreted Ts-RNF exhibits E3 ubiquitin ligase activity•Interaction of Ts-RNF with SQSTM1/P62 UBA domain•Interfering with the Ts-RNF gene can hinder the growth and development of T. spiralis•Ts-RNF hinders mitochondrial clearance and affects muscle differentiation Molecular biology; Musculoskeletal medicine; Parasitology