IDENTIFICATION OF AN ANTISENSE TRANSCRIPT FROM THE IGF-II LOCUS IN MOUSE

We have identified a novel antisense RNA transcribed from the insulin- like growth factor-II (IGF-II) locus in mouse. This transcript was ide ntified using probes derived from cloned genomic DNA lying between the insulin II locus and the IGF-II locus. S1 protection assays confirmed that this transcript is transcribed from the strand complementary to the stand encoding IGF-II. A 3.75 kb RNA was consistently detected on northern analysis of mouse tissue using different randomly primed DNA probes generated from this region. S1 nuclease protection analysis ide ntified three exons contained in the transcript. Developmental norther n analysis was performed using RNA from embryonic (E) and postnatal (P ) tissues of E10, E13, E18, P1, P4, P10, and adult mice. The antisense RNA was most abundant in E13 and E18 mouse and was present in greates t amounts in skull, skeletal muscle, cardiac muscle, and placenta. No signal for this RNA was detected after the fourth day of life in any t issue studied. (C) 1993 Wiley-Liss, Inc.