2bb2: Difference between revisions

Revision as of 17:35, 21 February 2008

X-RAY ANALYSIS OF BETA B2-CRYSTALLIN AND EVOLUTION OF OLIGOMERIC LENS PROTEINS

OverviewOverview

The beta, gamma-crystallins form a class of homologous proteins in the eye lens. Each gamma-crystallin comprises four topologically equivalent, Greek key motifs; pairs of motifs are organized around a local dyad to give domains and two similar domains are in turn related by a further local dyad. Sequence comparisons and model building predicted that hetero-oligomeric beta-crystallins also had internally quadruplicated subunits, but with extensions at the N and C termini, indicating that beta, gamma-crystallins evolved in two duplication steps from an ancestral protein folded as a Greek key. We report here the X-ray analysis at 2.1 A resolution of beta B2-crystallin homodimer which shows that the connecting peptide is extended and the two domains separated in a way quite unlike gamma-crystallin. Domain interactions analogous to those within monomeric gamma-crystallin are intermolecular and related by a crystallographic dyad in the beta B2-crystallin dimer. This shows how oligomers can evolve by conserving an interface rather than connectivity. A further interaction between dimers suggests a model for more complex aggregates of beta-crystallin in the lens.

About this StructureAbout this Structure

2BB2 is a Single protein structure of sequence from Bos taurus with as ligand. Full crystallographic information is available from OCA.

ReferenceReference

X-ray analysis of beta B2-crystallin and evolution of oligomeric lens proteins., Bax B, Lapatto R, Nalini V, Driessen H, Lindley PF, Mahadevan D, Blundell TL, Slingsby C, Nature. 1990 Oct 25;347(6295):776-80. PMID:2234050

Page seeded by OCA on Thu Feb 21 16:35:52 2008

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

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-[[Image:2bb2.jpg|left|200px]]<br /><applet load="2bb2" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:2bb2.jpg|left|200px]]<br /><applet load="2bb2" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="2bb2, resolution 2.1&Aring;" />
 '''X-RAY ANALYSIS OF BETA B2-CRYSTALLIN AND EVOLUTION OF OLIGOMERIC LENS PROTEINS'''<br />
 ==Overview==
-The beta, gamma-crystallins form a class of homologous proteins in the eye, lens. Each gamma-crystallin comprises four topologically equivalent, Greek, key motifs; pairs of motifs are organized around a local dyad to give, domains and two similar domains are in turn related by a further local, dyad. Sequence comparisons and model building predicted that, hetero-oligomeric beta-crystallins also had internally quadruplicated, subunits, but with extensions at the N and C termini, indicating that, beta, gamma-crystallins evolved in two duplication steps from an ancestral, protein folded as a Greek key. We report here the X-ray analysis at 2.1 A, resolution of beta B2-crystallin homodimer which shows that the connecting, peptide is extended and the two domains separated in a way quite unlike, gamma-crystallin. Domain interactions analogous to those within monomeric, gamma-crystallin are intermolecular and related by a crystallographic dyad, in the beta B2-crystallin dimer. This shows how oligomers can evolve by, conserving an interface rather than connectivity. A further interaction, between dimers suggests a model for more complex aggregates of, beta-crystallin in the lens.
+The beta, gamma-crystallins form a class of homologous proteins in the eye lens. Each gamma-crystallin comprises four topologically equivalent, Greek key motifs; pairs of motifs are organized around a local dyad to give domains and two similar domains are in turn related by a further local dyad. Sequence comparisons and model building predicted that hetero-oligomeric beta-crystallins also had internally quadruplicated subunits, but with extensions at the N and C termini, indicating that beta, gamma-crystallins evolved in two duplication steps from an ancestral protein folded as a Greek key. We report here the X-ray analysis at 2.1 A resolution of beta B2-crystallin homodimer which shows that the connecting peptide is extended and the two domains separated in a way quite unlike gamma-crystallin. Domain interactions analogous to those within monomeric gamma-crystallin are intermolecular and related by a crystallographic dyad in the beta B2-crystallin dimer. This shows how oligomers can evolve by conserving an interface rather than connectivity. A further interaction between dimers suggests a model for more complex aggregates of beta-crystallin in the lens.
 ==About this Structure==
-BB2 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with BME as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2BB2 OCA].
+BB2 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with <scene name='pdbligand=BME:'>BME</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2BB2 OCA].
 ==Reference==
@@ Line 14: / Line 14: @@
 [[Category: Single protein]]
 [[Category: Bax, B.]]
-[[Category: Blundell, T.L.]]
+[[Category: Blundell, T L.]]
 [[Category: Driessen, H.]]
 [[Category: Lapatto, R.]]
-[[Category: Lindley, P.F.]]
+[[Category: Lindley, P F.]]
 [[Category: Mahadevan, D.]]
 [[Category: Nalini, V.]]
@@ Line 24: / Line 24: @@
 [[Category: eye lens protein]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Wed Nov 21 08:41:22 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:35:52 2008''