Methods for identifying non-essential genes of the human cytomegalovirus genome and for screening for inhibitors of human cytomegalovirus

A method for identifying a compound which inhibits HCMV replication which comprises:

• (a) inserting a .beta.-glucuronidase marker gene into the HCMV genome to construct an HCMV recombinant in a manner selected from the group consisting of:
• (i) replacing a portion of a wild-type HCMV gene, such that the insertion of the marker gene prevents the expression of the product of the wild-type gene;
• (ii) adding to a wild-type HCMV gene, so as to disrupt the wild-type gene, such that the insertion of the marker gene prevents the expression of the product of the wild-type gene;
• (iii) replacing portions of two or more wild-type HCMV genes, such that the insertion of the .beta.-glucuronidase marker gene prevents the expression of the products of those wild-type genes;
• and
• (iv) inserting the .beta.-glucuronidase marker gene between two HCMV genes, such that no HCMV genes are replaced or disrupted and all HCMV gene products are expressed;
• (b) inserting the recombinant HCMV constructed in step (a) into a suitable mammalian host cell;
• (c) growing the host cell under suitable conditions to favor HCMV replication;
• (d) measuring the amount of any .beta.-glucuronidase produced;
• (e) repeating steps (c)-(d) in the presence of the test compound;
• and
• (f) comparing the results of (d) and (e), a reduction or inhibition of the amount of .beta.-glucuronidase produced in the presence of the test compound indicating that the test compound inhibits HCMV replication.