Biological Assembly 1  

 3D View: Structure | 1D-3D View | Validation Report | Ligand Interaction

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 17.11 kDa 
• Atom Count: 1191 
• Modelled Residue Count: 148 
• Deposited Residue Count: 148 
• Unique protein chains: 1

2LMT

NMR structure of Androcam

• PDB DOI: 10.2210/pdb2LMT/pdb
• BMRB: 17353

• Classification: METAL BINDING PROTEIN
• Organism(s): Drosophila melanogaster
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2011-12-12 Released: 2012-08-22 
• Deposition Author(s): Joshi, M.K., Moran, S.T., Beckingham, K.M., Mackenzie, K.R.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 50 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 

Literature

Structure of androcam supports specialized interactions with myosin VI.

Joshi, M.K., Moran, S., Beckingham, K.M., Mackenzie, K.R.

(2012) Proc Natl Acad Sci U S A 109: 13290-13295

• PubMed: 22851764 
• DOI: 10.1073/pnas.1209730109
• Primary Citation of Related Structures:  
  2LMT, 2LMU, 2LMV


• PubMed Abstract: 
  

Androcam replaces calmodulin as a tissue-specific myosin VI light chain on the actin cones that mediate D. melanogaster spermatid individualization. We show that the androcam structure and its binding to the myosin VI structural (Insert 2) and regulatory (IQ) light chain sites are distinct from those of calmodulin and provide a basis for specialized myosin VI function. The androcam N lobe noncanonically binds a single Ca(2+) and is locked in a "closed" conformation, causing androcam to contact the Insert 2 site with its C lobe only. Androcam replacing calmodulin at Insert 2 will increase myosin VI lever arm flexibility, which may favor the compact monomeric form of myosin VI that functions on the actin cones by facilitating the collapse of the C-terminal region onto the motor domain. The tethered androcam N lobe could stabilize the monomer through contacts with C-terminal portions of the motor or recruit other components to the actin cones. Androcam binds the IQ site at all calcium levels, constitutively mimicking a conformation adopted by calmodulin only at intermediate calcium levels. Thus, androcam replacing calmodulin at IQ will abolish a Ca(2+)-regulated, calmodulin-mediated myosin VI structural change. We propose that the N lobe prevents androcam from interfering with other calmodulin-mediated Ca(2+) signaling events. We discuss how gene duplication and mutations that selectively stabilize one of the many conformations available to calmodulin support the molecular evolution of structurally and functionally distinct calmodulin-like proteins.

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Organizational Affiliation: 

Department of Biochemistry and Cell Biology, Rice University, Houston, TX 77005, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Calmodulin-related protein 97A	A	148	Drosophila melanogaster	Mutation(s): 0  Gene Names: And, androcam, Camr97A, CG17769, Acam
UniProt
Find proteins for P49258 (Drosophila melanogaster) Explore P49258  Go to UniProtKB:  P49258

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CA	B [auth A], C [auth A]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 50 
• Conformers Submitted: 20 
• Selection Criteria: structures with the lowest energy 
• OLDERADO: 2LMT Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2011-12-12 
• Released Date: 2012-08-22 
Deposition Author(s): Joshi, M.K., Moran, S.T., Beckingham, K.M., Mackenzie, K.R.

Revision History  

• Version 1.0: 2012-08-22
  Type: Initial release
  
• Version 1.1: 2012-09-05
  Changes: Database references