Figure 3. Membralin KO mice die of motor neuron degeneration and consequent paresis.
(A) Gene trapping was used to generate membralin KO mice by inserting a trapping vector that contained a splicing acceptor sequence between exon 1 and 2 to disrupt normal RNA splicing. Primers (P1, P2, P3, red arrows) were designed to detect normal and trapped membralin transcripts. RT-PCR experiments showed that PCR products using the P1 and P3 primer pair were only detected in WT mouse brain (lane 1), liver (lane 2), and kidney (lane 3), whereas PCR products using the P1 and P2 primers were only detected in these tissues of KO mice. (B) Membralin KO mice phenocopied GluN3B/membralin DKO mice and died of paresis around P5. (C) Lumbar motor neurons, identified by anti-Hb9 staining (top panels), were significantly reduced (lower panel) in membralin KO mice compared to WT mice (n = 3 for each group of mice, *p < 0.05, Student's t-test). Data are mean +s.e.m.