FIG. 1.

Schematic representation of DNA constructs used in the present study. Promoter (p), terminator (t), and coding (c) regions of indicated genes are represented as boxes, and introns (i) as triangles. Bold arrows indicate the direction of transcription of the respective DNA element at the original locus, and the fine arrows indicate the transcriptional start sites of the constructs. The length of the longer DNA fragments is given in kilobases. Hatched boxes and block arrows below the boxes indicate hybridization probes used for Southern blot analyses and primers used for genomic PCR analyses, respectively. Restriction sites used for Southern blot analyses are indicated by thick (HindIII) or thin lines (HpaII/MspI).