Lefty-2 (Left-right determination factor 2; also Lefty-B [in human]) is a atypical member of the TGF-beta family of proteins. It is expressed during early embryogenesis in both the primitive streak and left-side lateral plate mesoderm. In the adult, Lefty-2 appears in oviduct epithelium. Lefty-2 acts in a manner reminiscent of that for Chordin and Noggin, and it is assumed that Lefty-2 is an antagonist of BMP activity. Notably, Lefty-2 and Nodal are likely under the control of Lefty-1, and thus all three molecules would appear to contribute to the creation of a left side-type body plan. Mouse Lefty-2 is synthesized as a 368 amino acid (aa) preproprecursor. It contains a 21aa signal sequence, plus a 347aa, 41-42kD bioactive proprecursor that may undergo proteolytic processing at one of two downstream cleavage sites. If cleavage occurs after Arg77, the resulting 33-34kD mature form (aa78-368) is biologically inactive; if cleavage occurs after Arg135, the resulting 27-28kD mature form (aa136-368) is biologically active. Lefty-2 is not a covalent homodimer and has been suggested to act as a monomer. Over aa78-368, mouse Lefty-2 shares 94%, 83% and 95% aa sequence identity with rat Lefty-2, human Lefty-B and mouse Lefty-1, respectively.
Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.