Fig. 1. LARM1 and LARM2 are conserved, bound by Lmx1b, and associated with active chromatin marks.

a UCSC genome screenshot displaying the Lmx1b locus and the associated cis-regulatory modules LARM1 and LARM2 (highlighted in blue) showing vertebrate conservation (VERT cons), Lmx1b binding (Lmx1b-targeted ChIP-seq)⁸ and input⁸. b Magnification of the putative enhancer region displaying the overlap with active enhancer-associated regulatory marks present in limb buds. From top to bottom: vertebrate conservation (VERT cons), ChIP-seq tracks for Lmx1b⁸, control Input limb DNA⁸, p300¹⁰, histone 3 acetylation at lysine 27 (H3K27Ac)¹¹, histone 3 dimethylation at lysine 4 (H3K4me2)¹², RNA polymerase II¹³, Med 12¹³, and histone 3 trimethylation at lysine 27 (H3K7me3)¹². Note that LARM1 consists of two conserved peaks, both of which are recognized by Lmx1b-targeted ChIP-seq⁸. Upstream of LARM2, another conserved region is present (asterisk). This potential cis-regulatory module is also associated with the 9430024E24Rik gene²¹, but does not appear to be bound by Lmx1b, as shown in the Lmx1b-targeted ChIP-seq track (see also Supplementary Fig. 2).