Sequence and expression of a baculovirus protein with antigenic similarity to telokin.

A protein from baculovirus-infected cells reacted with an antibody against the smooth muscle protein telokin. Because of this unusual similarity, the protein, termed telokin-like protein-20 (TLP20), was isolated and characterized. Its M(r) on denaturing polyacrylamide gels was 28K and the protein contained a high proportion of beta structure. A cDNA for TLP20 was isolated and sequenced. The 3' non-coding sequence contained a region of high identity with the 5' end of two other baculovirus genes. The 5' non-coding region contains several baculovirus regulatory elements. Surprisingly, the derived amino acid sequence showed no homologies to telokin. The cDNA was cloned into a bacterial expression vector and the subsequently expressed protein had a slightly lower M(r) than the native protein, but cross-reacted with telokin antibody. This paper reports the characterization of a new baculovirus protein that shares some antigenic similarities to the smooth muscle protein telokin.