PDBsum entry 4qpy

Protein binding

PDB id: 4qpy

Contents

Protein chains

131 a.a.

Waters ×112

PDB id:

4qpy

Name:

Protein binding

Title:

Crystal structure of c1ql2

Structure:

Complement c1q-like protein 2. Chain: a, b, c. Synonym: c1q and tumor necrosis factor-related protein 10, c1q/tnf- related protein 10, c1qtnf10, ctrp10. Engineered: yes

Source:

Mus musculus. Mouse. Organism_taxid: 10090. Gene: c1ql2, c1qtnf10, ctrp10. Expressed in: escherichia coli. Expression_system_taxid: 562.

Resolution:

2.38Å R-factor: 0.172 R-free: 0.216

Authors:

S.Ressl,A.T.Brunger

Key ref:

S.Ressl et al. (2015). Structures of C1q-like proteins reveal unique features among the C1q/TNF superfamily. Structure, 23, 688-699. PubMed id: 25752542 DOI: 10.1016/j.str.2015.01.019

Date:

25-Jun-14 Release date: 15-Apr-15

Protein chains

Q8CFR0  (C1QL2_MOUSE) -  Complement C1q-like protein 2 from Mus musculus

Seq: 287 a.a.

Struc: 131 a.a.

DOI no: 10.1016/j.str.2015.01.019

Structure 23:688-699 (2015)

PubMed id: 25752542

Structures of C1q-like proteins reveal unique features among the C1q/TNF superfamily.

S.Ressl, B.K.Vu, S.Vivona, D.C.Martinelli, T.C.Südhof, A.T.Brunger.

ABSTRACT

C1q-like (C1QL) -1, -2, and -3 proteins are encoded by homologous genes that are highly expressed in brain. C1QLs bind to brain-specific angiogenesis inhibitor 3 (BAI3), an adhesion-type G-protein coupled receptor that may regulate dendritic morphology by organizing actin filaments. To begin to understand the function of C1QLs, we determined high-resolution crystal structures of the globular C1q-domains of C1QL1, C1QL2, and C1QL3. Each structure is a trimer, with each protomer forming a jelly-roll fold consisting of 10 β strands. Moreover, C1QL trimers may assemble into higher-order oligomers similar to adiponectin and contain four Ca(2+)-binding sites along the trimeric symmetry axis, as well as additional surface Ca(2+)-binding sites. Mutation of Ca(2+)-coordinating residues along the trimeric symmetry axis lowered the Ca(2+)-binding affinity and protein stability. Our results reveal unique structural features of C1QLs among C1q/TNF superfamily proteins that may be associated with their specific brain functions.