R&D Systems Recombinant Human TGF-beta RII Isoform 2 Fc Chimera, CF (50 UG) Item ID: RDS1003RT050

Most cell types express three sizes of receptors for TGF-beta. These are designated Type I (53 kDa), Type II (70‑85 kDa) and Type III (250‑350 kDa). The Type III receptor, a proteoglycan that exists in membrane‑bound and soluble forms, binds TGF-beta 1, TGF-beta 2 and TGF-beta 3, and appears to participate in both TGF-beta dependent and independent cellular signaling. The Type II receptor, by contrast, is a membrane-bound serine/threonine kinase that binds TGF-beta 1 and TGF-beta 3 with high affinity, and TGF-beta 2 with a much lower affinity. The Type I receptor is also a membrane-bound serine/threonine kinase that requires the presence of the Type II receptor to bind TGF-beta. Evidence suggests that signal transduction requires the cytoplasmic domains of both the Type I and Type II receptors. TGF-beta receptor II isoform 2 (also TGF-beta RII isoform A) is an alternatively spliced variant of the standard Type II TGF-beta receptor (or TGF-beta RII isoform 1) that possesses a 27 amino acid substitution for Val10 near the N-terminus of the mature protein. Both T beta RII and T beta RII isoform 2 bind TGF-beta 1 and TGF-beta 3 with high affinity. However, only TGF-beta RII isoform 2 also binds TGF-beta 2 with high affinity in the absence of TGF‑ beta  RIII. While TGF-beta RII is widely expressed on cells, TGF-beta RII isoform 2 shows distinct expression pattern mainly associated with bone‑related cells, such as osteoblasts and mesenchymal precursor cells. TGF-beta RII isoform 2 may play an important role in TGF-beta 2 binding and signaling in cells lacking TGF-beta RIII.