In-situ hybridisation Complete cds for the ovine arginine-vasopressin (Avp) and vasoactive intestinal polypeptide (Vip) were cloned and deposited in GenBank. Homologous probes used in this paper are as follows: oFbxl3 covers nt 110–580 of EF643523, oFbxl21 covers nt 342– 709 of EU239380, oAvp covers nt 1–501 of EU045357, oVip covers nt 1–513 of EU016225, mFbxl3 covers nt 450–1175 of NM_015822, mFbxl21 covers nt 905–1656 of NM_178674. Hypothalamic blocks for in situ hybridisation were cut into 20 mm sections using a cryostat, and thaw-mounted onto poly- lysine and gelatin coated slides. Radioactive cRNA riboprobes were prepared by plasmid linearisation and in vitro transcription reactions including 35S-UTP (Perkin-Elmer). Sections were hybridized overnight at 60uC with 5.105 cpm of probe per slide, subjected to RNaseA digestion and stringency washes in sodium References 1. Reppert SM, Weaver DR (2002) Coordination of circadian timing in mammals. Nature 418: 935–941. 2. 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DeBruyne JP, Weaver DR, Reppert SM (2007) CLOCK and NPAS2 have overlapping roles in the suprachiasmatic circadian clock. Nat Neurosci 10: 543–545. PLoS ONE | www.plosone.org 8 October 2008 | Volume 3 | Issue 10 | e3530