FIG. 1.
Construction of recombinant virus with deletion of the vIL-8 gene. (A) The MDV genome consists of terminal repeat long (TRL) and short (TRS), internal repeat long (IRL) and short (IRS), and unique long (UL) and unique short (US) DNA segments. (B) Schematic representation of overlapping clones generated to reconstitute an infectious virus from a very virulent strain of MDV (Md5). The restriction enzymes used to generate each cosmid clone and their positions are indicated. (C) Cosmids SN5/ΔvIL8 and A6/ΔvIL8 have the vIL8 coding sequences deleted by ClaI and NcoI digestions. The locations of the restriction enzymes used to introduce the deletions are indicated.