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- ****************************************************
- * PTN/MK heparin-binding protein family signatures *
- ****************************************************
-
- The following extracellular heparin-binding proteins involved in regulation of
- growth and differentiation belong to a new family of growth factors:
-
- - Pleiotrophin (PTN) [1]. Also known as heparin-binding growth-associated
- molecule (HB-GAM), heparin-binding growth factor 8 (HBGF-8), heparin-
- binding neutrophic factor) (HBNF) and osteoblast specific protein (OSF-1).
- This factor has neurite extension activity.
- - Midkine (MK) [2], a retinoic acid-induced differentiation factor.
- - Retinoic acid-induced heparin-binding protein (RI-HB) [3] from chicken. RI-
- has mitogenic activity and neurite extension activity for PC12 cells. RI-HB
- is possibly the chicken homolog of mammalian MK.
-
- These growth factors are highly related proteins of about 140 amino acids that
- contain 10 conserved cysteines probably involved in disulfide bonds (their
- position is schematically represented in the figure below). These proteins are
- also rich in basic residues and in tryptophan.
-
- xxxxxxxCxxxCxxxCxxxxxCxxxCxCxxxxCxxxxCxxxxxxxxxxCxxxxCxxxxxxxxxxxxx
- ************* *************
-
- 'C': conserved cysteine probably involved in a disulfide bond.
- '*': position of the patterns.
-
- We developed two signature patterns for this family of growth factors. As
- shown in the figure above, the patterns include the majority of the conserved
- cysteines.
-
- -Consensus pattern: S-[DE]-C-x-[DE]-W-x-W-x(2)-C-x-P-x-[SN]-x-D-C-G-[LIVM]-G-
- x-R-E-G
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Consensus pattern: C-[KR]-[LIVM]-P-C-N-W-K-K-x-F-G-A-[DE]-C-K-Y-x-F-[EQ]-x-W-
- G-x-C
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Last update: October 1993 / Patterns and text revised.
-
- [ 1] Li Y.-S., Milner P.G., Chauhan A.K., Watson M.A., Hoffman R.M.,
- Kodner C.M., Milbrandt J., Deuel T.F.
- Science 250:1690-1693(1990).
- [ 2] Tsutsui J.-I., Uehara K., Kadomatsu K., Matsubara S., Muramatsu T.
- Biochem. Biophys. Res. Commun. 176:792-797(1991).
- [ 3] Urios P., Duprez D., Le Caer J.-P., Courtois Y., Vigny M., Laurent M.
- Biochem. Biophys. Res. Commun. 175:617-624(1991).
-