PDBsum entry 3g9a

Fluorescent protein/immune system

PDB id: 3g9a

Contents

Protein chains

227 a.a. *

129 a.a. *

Waters ×685

* Residue conservation analysis

PDB id:

3g9a

Name:

Fluorescent protein/immune system

Title:

Green fluorescent protein bound to minimizer nanobody

Structure:

Green fluorescent protein. Chain: a. Engineered: yes. Mutation: yes. Minimizer. Chain: b. Engineered: yes

Source:

Aequorea victoria. Jellyfish. Organism_taxid: 6100. Gene: gfp. Expressed in: escherichia coli. Expression_system_taxid: 562. Camelus dromedarius. Alpaca. Organism_taxid: 9838.

Resolution:

1.61Å R-factor: 0.162 R-free: 0.194

Authors:

A.Kirchhofer,J.Helma,K.Schmidthals,C.Frauer,S.Cui,A.Karcher,M.Pellis, S.Muyldermans,C.C.Delucci,M.C.Cardoso,H.Leonhardt,K.-P.Hopfner, U.Rothbauer

Key ref:

A.Kirchhofer et al. (2010). Modulation of protein properties in living cells using nanobodies. Nat Struct Biol, 17, 133-138. PubMed id: 20010839

Date:

13-Feb-09 Release date: 08-Dec-09

Protein chain

P42212  (GFP_AEQVI) -  Green fluorescent protein from Aequorea victoria

Seq: 238 a.a.

Struc: 227 a.a.*

Protein chain

No UniProt id for this chain

Struc: 129 a.a.

* PDB and UniProt seqs differ at 6 residue positions (black crosses)

Nat Struct Biol 17:133-138 (2010)

PubMed id: 20010839

Modulation of protein properties in living cells using nanobodies.

A.Kirchhofer, J.Helma, K.Schmidthals, C.Frauer, S.Cui, A.Karcher, M.Pellis, S.Muyldermans, C.S.Casas-Delucchi, M.C.Cardoso, H.Leonhardt, K.P.Hopfner, U.Rothbauer.

ABSTRACT

Protein conformation is critically linked to function and often controlled by interactions with regulatory factors. Here we report the selection of camelid-derived single-domain antibodies (nanobodies) that modulate the conformation and spectral properties of the green fluorescent protein (GFP). One nanobody could reversibly reduce GFP fluorescence by a factor of 5, whereas its displacement by a second nanobody caused an increase by a factor of 10. Structural analysis of GFP-nanobody complexes revealed that the two nanobodies induce subtle opposing changes in the chromophore environment, leading to altered absorption properties. Unlike conventional antibodies, the small, stable nanobodies are functional in living cells. Nanobody-induced changes were detected by ratio imaging and used to monitor protein expression and subcellular localization as well as translocation events such as the tamoxifen-induced nuclear localization of estrogen receptor. This work demonstrates that protein conformations can be manipulated and studied with nanobodies in living cells.