In silico study of the human rhodopsin and meta rhodopsin II/S-arrestin complexes: impact of single point mutations related to retina degenerative diseases.
We propose two models of the human S-arrestin/rhodopsin complex in the inactive dark adapted rhodopsin and meta rhodopsin II form, obtained by homology modeling and knowledge based docking. First, a homology model for the human S-arrestin was built and validated by molecular dynamics, showing an average root mean square deviation difference from the pattern behavior of 0.76 A. Then, combining the human S-arrestin model and the modeled structure of the two human rhodopsin forms, we propose two models of interaction for the human S-arrestin/rhodopsin complex. The models involve two S-arrestin regions related to the N domain (residues 68-78; 170-182) and a third constituent of the C domain (248-253), with the rhodopsin C terminus (330-348). Of the 22 single point mutations related to retinitis pigmentosa and congenital night blindness located in the cytoplasmatic portion of rhodopsin or in S-arrestin, our models locate 16 in the interaction region and relate two others to possible dimer formation. Our calculations also predict that the light activated complex is more stable than the dark adapted rhodopsin and, therefore, of higher affinity to S-arrestin.
Mokarzel-Falcón
Leonardo
L
Microbiology and Virology Department, Biology Faculty, Havana University, Havana 10400, Cuba.
Padrón-García
Juan Alexander
JA
Carrasco-Velar
Ramón
R
Berry
Colin
C
Montero-Cabrera
Luis A
LA
D019393:Arrestin / Q000235:genetics* / Q000378:metabolism; D019295:Computational Biology / Q000379:methods*; D006801:Humans; D008958:Models, Molecular; D046912:Multiprotein Complexes / Q000235:genetics; D017354:Point Mutation; D011485:Protein Binding; D012162:Retinal Degeneration / Q000209:etiology / Q000235:genetics*; D012243:Rhodopsin / Q000235:genetics* / Q000378:metabolism
D019393:Arrestin; D046912:Multiprotein Complexes; C013110:metarhodopsins; D012243:Rhodopsin