Virology, Nebraska Center for


Date of this Version



J Microbiol. 2003 ; 41(4): 295–299.


Copyright 2003 Joung et al.


Adenovirus (Ad) precursor to the terminal protein (pTP) plays an essential roles in the viral DNA

replication. Ad pTP serves as a primer for the synthesis of a new DNA strand during the initiation

step of replication. In addition, Ad pTP forms organized spherical replication foci on the nuclear

matrix (NM) and anchors the viral genome to the NM. Here we identified the interferon inducible

gene product 1-8D (Inid) as a pTP binding protein by using a two-hybrid screen of a HeLa cDNA

library. Of the clones obtained in this assay, nine were identical to the Inid, a 13-kDa polypeptide

that shares homology with genes 1-8U and Leu-13/9-27, most of which have little known functions.

The entire open reading frame (ORF) of Inid was cloned into the tetracycline inducible expression

vector in order to determine the biological functions related with adenoviral infection. When Inid

was introduced to the cells along with adenoviruses, fifty to sixty percent of Ad-infected cells

expressing Inid had rounded morphology, which was suggestive of apoptosis. Results from the

terminal deoxynucleotidyl transferase (TdT) and DNA fragmentation assays confirmed that Inid

induces apoptosis in Ad-infected or in uninfected cells. The Inid binding to pTP may target the cell

for apoptotic destruction as a host defense mechanism against the viral infection.