Figure 1.

Generation and characterization of 5-HT₇^−/− mice. (A) The genomic structure surrounding the interrupted exon II of the 5-HT₇ knockout construct. The exon was interrupted by inserting a neomycin cassette at a genomic MluI restriction site. The MluI and other relevant restriction sites used in generating the construct or for diagnostic use are shown. (B) Southern blot analysis of EcoRI/BglII-digested genomic DNA from six individual animals by using the external probe indicated to visualize ≈7-kb and 4.9-kb bands. (C) Northern blot analysis of total RNA extracted from six individual animals by using a probe recognizing exon II sequence to visualize wild-type mRNA. A large aberrant message is present in the 5-HT₇^+/− and 5-HT₇^−/− mice. (D) The same blot as in C showing that this message contains the neomycin cassette as visualized by a probe recognizing a 300-bp piece of the cassette.