Tg(PySTdeltaMT)82Poz

The transgene comprises 1.2 kb of the Polyomavirus (PyV) early region, including the PyV early promoter, followed by the SV40 VP1 intron and a 0.4 kb DNA fragment containing the downstream enhancer from the NB11/1 mutant PyV, which has a wide host cell type range. The protein coding region, in which overlapping sequences encode the small tumor (T) antigen (ST), middle T antigen (MT) and large T antigen (LT), is truncated so that while the full-length ST is expressed, the MT contains only the amino-terminal 304 amino acids (a.a.) of the 420 a.a. full-length protein; the truncated LT gene encodes only 196 a.a. of the full length 784 a.a. protein. RNAse protection analysis demonstrates high levels of the 3' 260 nt of the truncated coding sequence in total RNA from thyroid tumors and pre-neoplastic thyroid gland and from a wide variety of tissues in which no pathology is observed. The truncated MT and full length ST (but not the severely truncated LT) antigens are detected by immunoblot analysis of lysates of thyroid tumors, muscle, kidney and skin. (J:172189)