1JNE

Crystal structure of imaginal disc growth factor-2

1JNE の概要

• エントリーDOI: 10.2210/pdb1jne/pdb
• 分子名称: Imaginal disc growth factor-2, alpha-D-mannopyranose-(1-3)-beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose (3 entities in total)
• 機能のキーワード: idgf, imaginal disc, growth factor, chitinase, insulin receptor, heparin, hormone-growth factor complex, hormone/growth factor
• 由来する生物種: Drosophila melanogaster (fruit fly)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 47701.44

構造登録者

Varela, P.F.,Llera, A.S.,Mariuzza, R.A.,Tormo, J. (登録日: 2001-07-23, 公開日: 2002-05-01, 最終更新日: 2024-10-30)

主引用文献

Varela, P.F.,Llera, A.S.,Mariuzza, R.A.,Tormo, J.
Crystal structure of imaginal disc growth factor-2. A member of a new family of growth-promoting glycoproteins from Drosophila melanogaster.
J.Biol.Chem., 277:13229-13236, 2002

PubMed Abstract: Imaginal disc growth factor-2 (IDGF-2) is a member of a recently described family of Drosophila melanogaster-soluble polypeptide growth factors that promote cell proliferation in imaginal discs. Although their precise mode of action has not been established, IDGFs cooperate with insulin in stimulating the growth of imaginal disc cells. We report the crystal structure of IDGF-2 at 1.3-A resolution. The structure shows the classical (betaalpha)(8) barrel-fold of family 18 glycosyl hydrolases, with an insertion of an alpha + beta domain similar to that of Serratia marcescens chitinases A and B. However, amino acid substitutions in the consensus catalytic sequence of chitinases give IDGF-2 a less negatively charged environment in its putative ligand-binding site and preclude the nucleophilic attack mechanism of chitin hydrolysis. Particularly important is the replacement of Glu by Gln at position 132, which has been shown to abolish enzymatic activity in chitinases. Nevertheless, a modest conservation of residues that participate in oligosaccharide recognition suggests that IDGF-2 could bind carbohydrates, assuming several conformational changes to open the partially occluded binding site. Thus, IDGFs may have evolved from chitinases to acquire new functions as growth factors, interacting with cell surface glycoproteins implicated in growth-promoting processes, such as the Drosophila insulin receptor.

PubMed: 11821393
DOI: 10.1074/jbc.M110502200

実験手法

X-RAY DIFFRACTION (1.7 Å)