Epstein-Barr virus (EBV)-negative, Burkitt-like lymphoma-derived cells were transformed with a transducing vector (pSV2-gpt) containing the Escherichia coli gene coding for xanthine-guanine phosphoribosyltransferase (XGPRT) and with a derivative of PSV2-gpt that carries the genes for the EBV-associated small RNAs on the EcoRI J fragment of B95-8 EBV DNA inserted at the unique EcoRI site (pJ-gpt). Cells transformed with PSV2-gpt and pJ-gpt express the E. coli gpt gene to approximately the same extent, judged by determinations of the XGPRT activity of cell extracts. Blot hybridisation experiments with restriction endonuclease-cleaved DNA from the transformants have revealed the presence of vector DNA sequences in the cells, at least some of which are most probably integrated into high mol. wt. chromosomal DNA. Northern blot hybridisation analysis of cytoplasmic RNA from pJ-gpt-transformed cells revealed the presence of an EcoRI J DNA complementary RNA species of the same size as the EBV DNA-encoded small RNAs found in EBV-transformed cells.