Stabilization of interleukin-2 receptor alpha chain mRNA by HTLV-1 Rex in mouse L cells: lower amounts of Rex do not stabilize the mRNA.

T cell growth factor receptor, interleukin-2 receptor alpha chain (IL-2R alpha) is constitutively expressed on human T-cell leukemia virus type-1 (HTLV-1) infected T cells. We have established L cell lines which express both IL-2R alpha and the Rex protein of HTLV-1. We found that IL-1R alpha mRNA is stabilized in a cell line, Ltk/1-2a, which expresses a high amount of the Rex protein. In the presence of lower amounts of Rex, stabilization of the mRNA was not observed. These results may well explain the mechanism by which most of the lymphocytes infected with HTLV-1 escape from malignant transformation.