NUCLEOTIDE-SEQUENCE OF INFECTIOUS LARYNGOTRACHEITIS VIRUS (GALLID HERPESVIRUS-1) ICP4 GENE

The infectious laryngotracheitis virus (ILTV) gene encoding a homologu e to the ICP4 protein of herpes simplex virus (HSV) has been mapped to the inverted repeat region. The complete nucleotide sequence of ILTV ICP4 has been determined. The ILTV ORF encoding ICP4 is 4386 nucleotid es long, calculated from the first of four ATG codons, and has an over all G+C content of 59%. The ILTV ICP4 contains two domains of high hom ology which have been reported in other studies to be conserved in the ICP4 homologues of alphaherpesviruses, and to be functionally importa nt. Several regulatory features were identified including a serine-ric h domain in region one. A more extensive serine-rich domain was locate d in region five which is also found in varicella-zoster virus (VZV) a nd bovine herpesvirus 1. A 5.4 kb immediate early transcript was ident ified in infected primary kidney cells.