NUCLEOTIDE-SEQUENCE OF THE LEFT-TERMINUS OF INFECTIOUS LARYNGOTRACHEITIS VIRUS (GALLID HERPESVIRUS-1) SA-2 STRAIN

The nucleotide sequence of 10.6 kilobase pairs (kbp) at the left-termi nus of infectious laryngotracheitis virus (ILTV) SA-2 vaccine strain w as determined. Several features were elucidated, including, 102 base p air (bp) inverted repeats separated by 750 bp of unique sequence which contains an NF-1 binding site indicating that the terminal may be a s ite for an origin of replication. Other direct repeats were also found in this region. To the right of the inverted repeat region, a 2130 bp region was found to contain small open reading frames (ORFs) of less than 100 aa. Another potential ORF was found to the right of the regio n containing the small ORFs which consisted of two 184 bp direct repea ts inserted into the reading frame, which would truncate the putative product. Only one copy of this repeat was found in the corresponding h omologue of the wild type strain SA-O. Six other ORFs were found, whic h shared little or no identity to homologues of other alphaherpesvirus es, suggesting that these putative genes are unique to ILTV.