Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Hetero 4-mer - A2B2 

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

Macromolecule Content

• Total Structure Weight: 36.39 kDa 
• Atom Count: 2264 
• Residue Count: 287 
• Unique protein chains: 2

4B7Y

Crystal structure of the MSL1-MSL2 complex

• DOI: 10.2210/pdb4B7Y/pdb

• Classification: GENE REGULATION
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2012-08-24 Released: 2013-02-06 
• Deposition Author(s): Hallacli, E., Lipp, M., Georgiev, P., Spielman, C., Cusack, S., Akhtar, A., Kadlec, J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.25 Å
• R-Value Free: 0.260 
• R-Value Work: 0.244 
• R-Value Observed: 0.245 

Literature

Msl1-Mediated Dimerization of the Dosage Compensation Complex is Essential for Male X-Chromosome Regulation in Drosophila.

Hallacli, E., Lipp, M., Georgiev, P., Spielman, C., Cusack, S., Akhtar, A., Kadlec, J.

(2012) Mol Cell 48: 587

• PubMed: 23084835 
• DOI: 10.1016/j.molcel.2012.09.014
• Primary Citation of Related Structures:  
  4B7Y, 4B86


• PubMed Abstract: 
  

The Male-Specific Lethal (MSL) complex regulates dosage compensation of the male X chromosome in Drosophila. Here, we report the crystal structure of its MSL1/MSL2 core, where two MSL2 subunits bind to a dimer formed by two molecules of MSL1. Analysis of structure-based mutants revealed that MSL2 can only interact with the MSL1 dimer, but MSL1 dimerization is MSL2 independent. We show that Msl1 is a substrate for Msl2 E3 ubiquitin ligase activity. ChIP experiments revealed that Msl1 dimerization is essential for targeting and spreading of the MSL complex on X-linked genes; however, Msl1 binding to promoters of male and female cells is independent of the dimer status and other MSL proteins. Finally, we show that loss of Msl1 dimerization leads to male-specific lethality. We propose that Msl1-mediated dimerization of the entire MSL complex is required for Msl2 binding, X chromosome recognition, and spreading along the X chromosome.

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Organizational Affiliation: 

Max-Planck-Institut für Immunbiologie und Epigenetik, Stübeweg 51, 79108 Freiburg im Breisgau, Germany.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
MALE-SPECIFIC LETHAL 1 HOMOLOG	A, B	44	Homo sapiens	Mutation(s): 0  Gene Names: MSL1, MSL1L1
Find proteins for Q68DK7 (Homo sapiens) Explore Q68DK7  Go to UniProtKB:  Q68DK7
NIH Common Fund Data Resources
PHAROS:  Q68DK7 GTEx:  ENSG00000188895

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
MALE-SPECIFIC LETHAL 2 HOMOLOG	C, D	116	Homo sapiens	Mutation(s): 0  Gene Names: MSL2, KIAA1585, MSL2L1, RNF184 EC: 2.3.2
Find proteins for Q9HCI7 (Homo sapiens) Explore Q9HCI7  Go to UniProtKB:  Q9HCI7
NIH Common Fund Data Resources
PHAROS:  Q9HCI7 GTEx:  ENSG00000174579

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
ZN	C, D	ZINC ION Zn PTFCDOFLOPIGGS-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.25 Å
• R-Value Free: 0.260 
• R-Value Work: 0.244 
• R-Value Observed: 0.245 
• Space Group: P 3₂ 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 100.99	α = 90
b = 100.99	β = 90
c = 88.65	γ = 120

Software Package:

Software Name	Purpose
REFMAC	refinement
XDS	data reduction
XSCALE	data scaling
PHASER	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2012-08-24 
• Released Date: 2013-02-06 
Deposition Author(s): Hallacli, E., Lipp, M., Georgiev, P., Spielman, C., Cusack, S., Akhtar, A., Kadlec, J.

Revision History 

• Version 1.0: 2013-02-06
  Type: Initial release