2BV2

beta gamma crystallin from Ciona Intestinalis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.55 Å
  • R-Value Free: 0.245 
  • R-Value Work: 0.169 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Urochordate Betagamma-Crystallin and the Evolutionary Origin of the Vertebrate Eye Lens.

Shimeld, S.M.Purkiss, A.G.Dirks, R.P.H.Bateman, O.A.Slingsby, C.Lubsen, N.H.

(2005) Curr.Biol. 15: 1684

  • DOI: 10.1016/j.cub.2005.08.046

  • PubMed Abstract: 
  • A refracting lens is a key component of our image-forming camera eye; however, its evolutionary origin is unknown because precursor structures appear absent in nonvertebrates. The vertebrate betagamma-crystallin genes encode abundant structural prote ...

    A refracting lens is a key component of our image-forming camera eye; however, its evolutionary origin is unknown because precursor structures appear absent in nonvertebrates. The vertebrate betagamma-crystallin genes encode abundant structural proteins critical for the function of the lens. We show that the urochordate Ciona intestinalis, which split from the vertebrate lineage before the evolution of the lens, has a single gene coding for a single domain monomeric betagamma-crystallin. The crystal structure of Ciona betagamma-crystallin is very similar to that of a vertebrate betagamma-crystallin domain, except for paired, occupied calcium binding sites. The Ciona betagamma-crystallin is only expressed in the palps and in the otolith, the pigmented sister cell of the light-sensing ocellus. The Ciona betagamma-crystallin promoter region targeted expression to the visual system, including lens, in transgenic Xenopus tadpoles. We conclude that the vertebrate betagamma-crystallins evolved from a single domain protein already expressed in the neuroectoderm of the prevertebrate ancestor. The conservation of the regulatory hierarchy controlling betagamma-crystallin expression between organisms with and without a lens shows that the evolutionary origin of the lens was based on co-option of pre-existing regulatory circuits controlling the expression of a key structural gene in a primitive light-sensing system.


    Organizational Affiliation

    Department of Zoology, University of Oxford, The Tinbergen Building, South Parks Road, Oxford OX1 3PS, United Kingdom. sebastian.shimeld@zoo.ox.ac.uk




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CIONA BETAGAMMA-CRYSTALLIN
A, B
83N/AN/A
Protein Feature View is not available: No corresponding UniProt sequence found.
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

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A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
ACT
Query on ACT

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Download CCD File 
A
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
CA
Query on CA

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Download CCD File 
A, B
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.55 Å
  • R-Value Free: 0.245 
  • R-Value Work: 0.169 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 98.037α = 90.00
b = 29.788β = 121.48
c = 57.278γ = 90.00
Software Package:
Software NamePurpose
MOSFLMdata reduction
REFMACrefinement
PHASERphasing
SCALAdata scaling

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-09-29
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-07-12
    Type: Derived calculations