8A4F

Human Interleukin-4 mutant - C3T-IL4

8A4F の概要

• エントリーDOI: 10.2210/pdb8a4f/pdb
• 関連するPDBエントリー: 1ITM
• NMR情報: BMRB: 34736
• 分子名称: Interleukin-4 (1 entity in total)
• 機能のキーワード: cytokine, interleukin-4, il-4, disulphide mutant, c3t, 4-helix bundle, backbone dynamics, molecular dynamics
• 由来する生物種: Homo sapiens (human)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 14987.21

構造登録者

Vaz, D.C.,Rodrigues, J.R.,Mueller, T.D.,Sebald, W.,Redfield, C.,Brito, R.M.M. (登録日: 2022-06-11, 公開日: 2023-10-18, 最終更新日: 2024-10-16)

主引用文献

Vaz, D.C.,Rodrigues, J.R.,Loureiro-Ferreira, N.,Muller, T.D.,Sebald, W.,Redfield, C.,Brito, R.M.M.
Lessons on protein structure from interleukin-4: All disulfides are not created equal.
Proteins, 92:219-235, 2024

PubMed Abstract: Interleukin-4 (IL-4) is a hematopoietic cytokine composed by a four-helix bundle stabilized by an antiparallel beta-sheet and three disulfide bonds: Cys3-Cys127, Cys24-Cys65, and Cys46-Cys99. IL-4 is involved in several immune responses associated to infection, allergy, autoimmunity, and cancer. Besides its physiological relevance, IL-4 is often used as a "model" for protein design and engineering. Hence, to understand the role of each disulfide in the structure and dynamics of IL-4, we carried out several spectroscopic analyses (circular dichroism [CD], fluorescence, nuclear magnetic resonance [NMR]), and molecular dynamics (MD) simulations on wild-type IL-4 and four IL-4 disulfide mutants. All disulfide mutants showed loss of structure, altered interhelical angles, and looser core packings, showing that all disulfides are relevant for maintaining the overall fold and stability of the four-helix bundle motif, even at very low pH. In the absence of the disulfide connecting both protein termini Cys3-Cys127, C3T-IL4 showed a less packed protein core, loss of secondary structure (~9%) and fast motions on the sub-nanosecond time scale (lower S order parameters and larger τ correlation time), especially at the two protein termini, loops, beginning of helix A and end of helix D. In the absence of Cys24-Cys65, C24T-IL4 presented shorter alpha-helices (14% loss in helical content), altered interhelical angles, less propensity to form the small anti-parallel beta-sheet and increased dynamics. Simultaneously deprived of two disulfides (Cys3-Cys127 and Cys24-Cys65), IL-4 formed a partially folded "molten globule" with high 8-anilino-1-naphtalenesulphonic acid-binding affinity and considerable loss of secondary structure (~50%decrease), as shown by the far UV-CD, NMR, and MD data.

PubMed: 37814578
DOI: 10.1002/prot.26611

実験手法

SOLUTION NMR