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H Transfected Only Rabbit IgG

Western blot analysis of extracts from 293 cells, mock transfected (-) or transfected with a construct expressing Myc/DDK-tagged full-length human Lefty1 (hLefty1-Myc/DDK; +), using Lefty1 (D7E3G) Rabbit mAb (upper) and β-Actin (D6A8) Rabbit mAb #8457 (lower).

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Product Usage Information

Application Dilutions
Western Blotting 1:1000

Storage: Supplied in 10 mM sodium HEPES (pH 7.5), 150 mM NaCl, 100 µg/ml BSA, 50% glycerol and less than 0.02% sodium azide. Store at –20°C. Do not aliquot the antibody.

Specificity / Sensitivity

Lefty1 (D7E3G) Rabbit mAb recognizes transfected levels of total lefty1 protein.

Species Reactivity: Human
Species predicted to react based on 100% sequence homology: Mouse, Rat, Monkey

Source / Purification

Monoclonal antibody is produced by immunizing animals with a synthetic peptide corresponding to residues surrounding Pro108 of human lefty1 protein.

Lefty proteins are members of the TGF-β family of cell signaling molecules that are involved in growth and development (1,2). Named for their role in left-right axis determination and their exclusive expression on the left side of the developing mouse embryo, lefty1 and lefty2 contain a cysteine-knot motif that is characteristic of TGF-β related proteins, but lack an alpha-helix and a cysteine residue critical for ligand dimerization (3). Early in vertebrate embryogenesis, lefty represses TGF-β signaling by inhibiting the phosphorylation of Smad2 following activation of the TGF-β receptor (4). Down-regulated very early upon differentiation (5), lefty proteins act as extracellular antagonists of the signaling pathway for Nodal, a TGF-β ligand critical for left-right patterning and formation of the mesoderm and endoderm (6). Similar to other members of the TGF-β superfamily, lefty proproteins undergo cleavage to release a bioactive protein (7). The biologically active 42 kDa lefty precursor and the 28 kDa polypeptide have been shown to induce MAPK activity (7).

1.  Kingsley, D.M. (1994) Genes Dev 8, 133-46.

2.  Heldin, C.H. et al. (1997) Nature 390, 465-71.

3.  Meno, C. et al. (1997) Genes Cells 2, 513-24.

4.  Ulloa, L. and Tabibzadeh, S. (2001) J Biol Chem 276, 21397-404.

5.  Besser, D. (2004) J Biol Chem 279, 45076-84.

6.  Schier, A.F. (2003) Annu Rev Cell Dev Biol 19, 589-621.

7.  Ulloa, L. et al. (2001) J Biol Chem 276, 21387-96.

Entrez-Gene Id 10637
Swiss-Prot Acc. O75610

For Research Use Only. Not For Use In Diagnostic Procedures.
Cell Signaling Technology is a trademark of Cell Signaling Technology, Inc.

Lefty1 (D7E3G) Rabbit mAb