Identification of a TEAD homolog from Litopenaeus vannamei in response to WSSV infection

Transcription factors of TEAD (transcriptional enhanced associate domain) family are the downstream nuclear effector of Hippo signaling pathway, which play a pivotal regulatory role in cell proliferation, apoptosis, tumor formation and antiviral immunity. Here, we cloned and characterized a novel homolog of TEAD family from Litopenaeus vannamei for the first time, designed as LvScalloped. LvScalloped had an open reading frame of 1155 bp, which contained a TEA/ATTS DNA-binding domain and a Yes-associated binding domain. It was ubiquitously expressed in all tested tissues, and especially abundant in the intestine. Upon WSSV infection, the transcriptional levels of LvScalloped were found to be up-regulated significantly in the gills and hepatopancreas. To clarify its role in WSSV infection, dsRNA-mediated RNAi was performed. Results showed that inhibition of LvScalloped transcription reduced the transcription of viral genes (ie1 and vp28) and also the mortality of L. vannamei after WSSV challenge. Further investigation revealed that LvScalloped could induce the activity of the immediate-early viral gene wsv083 promoter. Additionally, co-immunoprecipitation and CCK8 assay demonstrated that the interaction of LvScalloped and its transcriptional co-activator LvYorkie was involved in the regulation of cell viability in High Five cells. The study revealed that LvScalloped might be manipulated by WSSV for its propagation and played a pivotal role in viral gene transcription and cell viability. It will provide information for an in-depth understanding of virus-host interactions and the functional mechanism of Hippo signaling pathway in shrimp.