1D1J

CRYSTAL STRUCTURE OF HUMAN PROFILIN II

1D1J の概要

• エントリーDOI: 10.2210/pdb1d1j/pdb
• 分子名称: PROFILIN II, SULFATE ION, 1-(2-METHOXY-ETHOXY)-2-{2-[2-(2-METHOXY-ETHOXY]-ETHOXY}-ETHANE, ... (5 entities in total)
• 機能のキーワード: acidic profilin isoform, actin-binding protein, poly-l-proline binding protein, contractile protein
• 由来する生物種: Homo sapiens (human)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 60721.22

構造登録者

Nodelman, I.M.,Bowman, G.D.,Lindberg, U.,Schutt, C.E. (登録日: 1999-09-17, 公開日: 2000-12-22, 最終更新日: 2024-02-07)

主引用文献

Nodelman, I.M.,Bowman, G.D.,Lindberg, U.,Schutt, C.E.
X-ray structure determination of human profilin II: A comparative structural analysis of human profilins.
J.Mol.Biol., 294:1271-1285, 1999

PubMed Abstract: Human profilins are multifunctional, single-domain proteins which directly link the actin microfilament system to a variety of signalling pathways via two spatially distinct binding sites. Profilin binds to monomeric actin in a 1:1 complex, catalyzes the exchange of the actin-bound nucleotide and regulates actin filament barbed end assembly. Like SH3 domains, profilin has a surface-exposed aromatic patch which binds to proline-rich peptides. Various multidomain proteins including members of the Ena/VASP and formin families localize profilin:actin complexes through profilin:poly-L-proline interactions to particular cytoskeletal locations (e.g. focal adhesions, cleavage furrows). Humans express a basic (I) and an acidic (II) isoform of profilin which exhibit different affinities for peptides and proteins rich in proline residues. Here, we report the crystallization and X-ray structure determination of human profilin II to 2.2 A. This structure reveals an aromatic extension of the previously defined poly-L-proline binding site for profilin I. In contrast to serine 29 of profilin I, tyrosine 29 in profilin II is capable of forming an additional stacking interaction and a hydrogen bond with poly-L-proline which may account for the increased affinity of the second isoform for proline-rich peptides. Differential isoform specificity for proline-rich proteins may be attributed to the differences in charged and hydrophobic residues in and proximal to the poly-L-proline binding site. The actin-binding face remains nearly identical with the exception of five amino acid differences. These observations are important for the understanding of the functional and structural differences between these two classes of profilin isoforms.

PubMed: 10600384
DOI: 10.1006/jmbi.1999.3318

実験手法

X-RAY DIFFRACTION (2.2 Å)