Figure 1.

Identification of Sh3gl2 as a transcript that is highly enriched in the bladder urothelium. (A) SymAtlas screenshot of microarray hybridization analysis for Sh3gl2 in mouse organs illustrating high signal intensity in tissues from the nervous system, as well as the bladder (circled in green). (B) Semiquantitative real-time RT-PCR analysis of selected mouse tissues verified enrichment of Sh3gl2 mRNA in the nervous system tissue and bladder. Data are presented as expression level relative to that in heart (following normalization to GAPDH), which is assigned a value of 1, and represent mean ± SD of triplicate values. (C) cDNAs prepared from urothelium, stroma, and detrusor smooth muscle tissue microdissected from mouse bladders were analyzed for expression of Sh3gl2 as well as the urothelial marker uroplakin 2 and the smooth muscle marker smooth muscle myosin heavy chain by semiquantitative real-time RT-PCR. As shown in the left panel, Sh3gl2 was expressed predominantly in the urothelium, with minimal mRNA detectable in stroma or detrusor smooth muscle. Effective separation of urothelial, stromal, and smooth muscle tissue by laser capture microdissection was demonstrated by restricted expression of uroplakin 2 and smooth muscle myosin heavy chain to urothelial and smooth muscle tissues, respectively (right panel). (D) IHC staining of mouse bladder tissue revealed Sh3gl2 expression to be restricted to the urothelium (b, d), with no signal evident in submucosa or muscle. Preincubation of primary antibody with blocking peptide eliminated signal completely (c), confirming antibody specificity. No background signal was detected in sections receiving secondary antibody only (a). Scale bar, 100 µm.