|
|
| Line 1: |
Line 1: |
| [[Image:1l6e.gif|left|200px]] | | {{Seed}} |
| | [[Image:1l6e.png|left|200px]] |
|
| |
|
| <!-- | | <!-- |
| Line 9: |
Line 10: |
| {{STRUCTURE_1l6e| PDB=1l6e | SCENE= }} | | {{STRUCTURE_1l6e| PDB=1l6e | SCENE= }} |
|
| |
|
| '''Solution structure of the docking and dimerization domain of protein kinase A II-alpha (RIIalpha D/D). Alternatively called the N-terminal dimerization domain of the regulatory subunit of protein kinase A.'''
| | ===Solution structure of the docking and dimerization domain of protein kinase A II-alpha (RIIalpha D/D). Alternatively called the N-terminal dimerization domain of the regulatory subunit of protein kinase A.=== |
|
| |
|
|
| |
|
| ==Overview==
| | <!-- |
| The structure of the N-terminal docking and dimerization domain of the type IIalpha regulatory subunit (RIIalpha D/D) of protein kinase A (PKA) forms a noncovalent stand-alone X-type four-helix bundle structural motif, consisting of two helix-loop-helix monomers. RIIalpha D/D possesses a strong hydrophobic core and two distinct, exposed faces. A hydrophobic face with a groove is the site of protein-protein interactions necessary for subcellular localization. A highly charged face, opposite to the former, may be involved in regulation of protein-protein interactions as a result of changes in phosphorylation state of the regulatory subunit. Although recent studies have addressed the hydrophobic character of packing of RIIalpha D/D and revealed the function of the hydrophobic face as the binding site to A-kinase anchoring proteins (AKAPs), little attention has been paid to the charges involved in structure and function. To examine the electrostatic character of the structure of RIIalpha D/D we have predicted mean apparent pKa values, based on Poisson-Boltzmann electrostatic calculations, using an ensemble of calculated dimer structures. We propose that the helix promoting sequence Glu34-X-X-X-Arg38 stabilizes the second helix of each monomer, through the formation of a (i, i +4) side chain salt bridge. We show that a weak inter-helical hydrogen bond between Tyr35-Glu19 of each monomer contributes to tertiary packing and may be responsible for discriminating from alternative quaternary packing of the two monomers. We also show that an inter-monomer hydrogen bond between Asp30-Arg40 contributes to quaternary packing. We propose that the charged face comprising of Asp27-Asp30-Glu34-Arg38-Arg40-Glu41-Arg43-Arg44 may be necessary to provide flexibility or stability in the region between the C-terminus and the interdomain/autoinhibitory sequence of RIIalpha, depending on the activation state of PKA. We also discuss the structural requirements necessary for the formation of a stacked (rather than intertwined) dimer, which has consequences for the orientation of the functionally important and distinct faces. | | The line below this paragraph, {{ABSTRACT_PUBMED_11985580}}, adds the Publication Abstract to the page |
| | (as it appears on PubMed at http://www.pubmed.gov), where 11985580 is the PubMed ID number. |
| | --> |
| | {{ABSTRACT_PUBMED_11985580}} |
|
| |
|
| ==About this Structure== | | ==About this Structure== |
| 1L6E is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1L6E OCA]. | | 1L6E is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1L6E OCA]. |
|
| |
|
| ==Reference== | | ==Reference== |
| Line 34: |
Line 38: |
| [[Category: Helix-loop-helix]] | | [[Category: Helix-loop-helix]] |
| [[Category: Regulatory subunit]] | | [[Category: Regulatory subunit]] |
| ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 23:35:24 2008'' | | |
| | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jul 2 11:48:05 2008'' |
