2DG2

Crystal Structure of Mouse Apolipoprotein A-I Binding Protein


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.206 
  • R-Value Observed: 0.207 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Biochemical and structural characterization of apolipoprotein A-I binding protein, a novel phosphoprotein with a potential role in sperm capacitation.

Jha, K.N.Shumilin, I.A.Digilio, L.C.Chertihin, O.Zheng, H.Schmitz, G.Visconti, P.E.Flickinger, C.J.Minor, W.Herr, J.C.

(2008) Endocrinology 149: 2108-2120

  • DOI: 10.1210/en.2007-0582
  • Primary Citation of Related Structures:  
    2DG2, 2O8N

  • PubMed Abstract: 
  • The physiological changes that sperm undergo in the female reproductive tract rendering them fertilization-competent constitute the phenomenon of capacitation. Cholesterol efflux from the sperm surface and protein kinase A (PKA)-dependent phosphorylation play major regulatory roles in capacitation, but the link between these two phenomena is unknown ...

    The physiological changes that sperm undergo in the female reproductive tract rendering them fertilization-competent constitute the phenomenon of capacitation. Cholesterol efflux from the sperm surface and protein kinase A (PKA)-dependent phosphorylation play major regulatory roles in capacitation, but the link between these two phenomena is unknown. We report that apolipoprotein A-I binding protein (AI-BP) is phosphorylated downstream to PKA activation, localizes to both sperm head and tail domains, and is released from the sperm into the media during in vitro capacitation. AI-BP interacts with apolipoprotein A-I, the component of high-density lipoprotein involved in cholesterol transport. The crystal structure demonstrates that the subunit of the AI-BP homodimer has a Rossmann-like fold. The protein surface has a large two compartment cavity lined with conserved residues. This cavity is likely to constitute an active site, suggesting that AI-BP functions as an enzyme. The presence of AI-BP in sperm, its phosphorylation by PKA, and its release during capacitation suggest that AI-BP plays an important role in capacitation possibly providing a link between protein phosphorylation and cholesterol efflux.


    Organizational Affiliation

    Center for Research in Contraceptive and Reproductive Health, Department of Cell Biology, University of Virginia, Charlottesville, Virginia 22908, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Apolipoprotein A-I binding proteinA, B, C, D, E, F265Mus musculusMutation(s): 7 
Gene Names: Apoa1bpNaxeAibp
EC: 5.1.99.6
UniProt & NIH Common Fund Data Resources
Find proteins for Q8K4Z3 (Mus musculus)
Explore Q8K4Z3 
Go to UniProtKB:  Q8K4Z3
IMPC:  MGI:2180167
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.206 
  • R-Value Observed: 0.207 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 104.855α = 90
b = 125.745β = 106.56
c = 163.62γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
HKL-3000data reduction
HKL-3000data scaling
HKL-3000phasing
SHELXDphasing
SHELXEmodel building
MLPHAREphasing
DMphasing
SOLVEphasing
RESOLVEphasing
Omodel building
Cootmodel building
CCP4phasing

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2007-03-27
    Type: Initial release
  • Version 1.1: 2008-04-30
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2017-10-11
    Changes: Refinement description