Biological Assembly 1  

 3D View: Structure | Ligand Interaction

Global Symmetry: Helical - H  (3D View)
Global Stoichiometry: Hetero 12-mer - A6B6 Pseudo Symmetry: Helical - H  (3D View)
Pseudo Stoichiometry: Homo 12-mer - A12 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 584.96 kDa 
• Atom Count: 40470 
• Modelled Residue Count: 5124 
• Deposited Residue Count: 5178 
• Unique protein chains: 2

5N5N

Cryo-EM structure of tsA201 cell alpha1B and betaI and betaIVb microtubules

• DOI: 10.2210/pdb5N5N/pdb
• EMDataResource: EMD-3589

• Classification: STRUCTURAL PROTEIN
• Organism(s): Homo sapiens
• Expression System: Homo sapiens
• Mutation(s): No 


• Deposited: 2017-02-14 Released: 2017-11-01 
• Deposition Author(s): Vemu, A., Atherton, J., Spector, J.O., Moores, C.A., Roll-Mecak, A.
• Funding Organization(s): Medical Research Council (United Kingdom), Intramural Programs of the NINDS and the NHLBI, National Institutes of Health

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 4.20 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Tubulin isoform composition tunes microtubule dynamics.

Vemu, A., Atherton, J., Spector, J.O., Moores, C.A., Roll-Mecak, A.

(2017) Mol Biol Cell 28: 3564-3572

• PubMed: 29021343 
• DOI: 10.1091/mbc.E17-02-0124
• Primary Citation of Related Structures:  
  5N5N


• PubMed Abstract: 
  

Microtubules polymerize and depolymerize stochastically, a behavior essential for cell division, motility, and differentiation. While many studies advanced our understanding of how microtubule-associated proteins tune microtubule dynamics in trans, we have yet to understand how tubulin genetic diversity regulates microtubule functions. The majority of in vitro dynamics studies are performed with tubulin purified from brain tissue. This preparation is not representative of tubulin found in many cell types. Here we report the 4.2-Å cryo-electron microscopy (cryo-EM) structure and in vitro dynamics parameters of α1B/βI+βIVb microtubules assembled from tubulin purified from a human embryonic kidney cell line with isoform composition characteristic of fibroblasts and many immortalized cell lines. We find that these microtubules grow faster and transition to depolymerization less frequently compared with brain microtubules. Cryo-EM reveals that the dynamic ends of α1B/βI+βIVb microtubules are less tapered and that these tubulin heterodimers display lower curvatures. Interestingly, analysis of EB1 distributions at dynamic ends suggests no differences in GTP cap sizes. Last, we show that the addition of recombinant α1A/βIII tubulin, a neuronal isotype overexpressed in many tumors, proportionally tunes the dynamics of α1B/βI+βIVb microtubules. Our study is an important step toward understanding how tubulin isoform composition tunes microtubule dynamics.

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Organizational Affiliation: 

Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, MD 20892.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Tubulin beta chain	H [auth A], A [auth B], I [auth C], J [auth D], K [auth E], L [auth F]	426	Homo sapiens	Mutation(s): 0  Gene Names: TUBB, TUBB5, OK/SW-cl.56
UniProt & NIH Common Fund Data Resources
Find proteins for P07437 (Homo sapiens) Explore P07437  Go to UniProtKB:  P07437
PHAROS:  P07437 GTEx:  ENSG00000196230

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Tubulin alpha-1B chain	C [auth G], D [auth H], E [auth I], F [auth J], B [auth K], G [auth L]	437	Homo sapiens	Mutation(s): 0  Gene Names: TUBA1B
UniProt & NIH Common Fund Data Resources
Find proteins for P68363 (Homo sapiens) Explore P68363  Go to UniProtKB:  P68363
PHAROS:  P68363 GTEx:  ENSG00000123416

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GTP	O [auth K], Q [auth G], S [auth H], U [auth I], W [auth J], Y [auth L]	GUANOSINE-5'-TRIPHOSPHATE C10 H16 N5 O14 P3 XKMLYUALXHKNFT-UUOKFMHZSA-N
G2P	AA [auth A], CA [auth C], EA [auth D], GA [auth E], IA [auth F], M [auth B]	PHOSPHOMETHYLPHOSPHONIC ACID GUANYLATE ESTER C11 H18 N5 O13 P3 GXTIEXDFEKYVGY-KQYNXXCUSA-N
MG	BA [auth A],  DA [auth C],  FA [auth D],  HA [auth E],  JA [auth F],  N [auth B],  P [auth K],  R [auth G],  T [auth H],  V [auth I],  X [auth J],  Z [auth L]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 4.20 Å
• Aggregation State: FILAMENT 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2017-02-14 
• Released Date: 2017-11-01 
Deposition Author(s): Vemu, A., Atherton, J., Spector, J.O., Moores, C.A., Roll-Mecak, A.

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Funding Organization	Location	Grant Number
Medical Research Council (United Kingdom)	United Kingdom	--
Intramural Programs of the NINDS and the NHLBI, National Institutes of Health	United States	--

Revision History  

• Version 1.0: 2017-11-01
  Type: Initial release
  
• Version 1.1: 2017-12-13
  Changes: Database references
• Version 1.2: 2018-10-17
  Changes: Data collection, Refinement description
• Version 1.3: 2019-10-23
  Changes: Data collection, Other