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2o8n
From Proteopedia
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'''Crystal Structure of Mouse Apolipoprotein A-I Binding Protein''' | '''Crystal Structure of Mouse Apolipoprotein A-I Binding Protein''' | ||
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| + | ==Overview== | ||
| + | The physiological changes that sperm undergo in the female reproductive tract rendering them fertilization-competent constitute the phenomenon of capacitation. Cholesterol efflux from the sperm surface and protein kinase A (PKA)-dependent phosphorylation play major regulatory roles in capacitation, but the link between these two phenomena is unknown. We report that apolipoprotein A-I binding protein (AI-BP) is phosphorylated downstream to PKA activation, localizes to both sperm head and tail domains, and is released from the sperm into the media during in vitro capacitation. AI-BP interacts with apolipoprotein A-I, the component of high-density lipoprotein involved in cholesterol transport. The crystal structure demonstrates that the subunit of the AI-BP homodimer has a Rossmann-like fold. The protein surface has a large two compartment cavity lined with conserved residues. This cavity is likely to constitute an active site, suggesting that AI-BP functions as an enzyme. The presence of AI-BP in sperm, its phosphorylation by PKA, and its release during capacitation suggest that AI-BP plays an important role in capacitation possibly providing a link between protein phosphorylation and cholesterol efflux. | ||
==About this Structure== | ==About this Structure== | ||
2O8N 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=2O8N OCA]. | 2O8N 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=2O8N OCA]. | ||
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| + | ==Reference== | ||
| + | Biochemical and structural characterization of apolipoprotein A-I binding protein, a novel phosphoprotein with a potential role in sperm capacitation., Jha KN, Shumilin IA, Digilio LC, Chertihin O, Zheng H, Schmitz G, Visconti PE, Flickinger CJ, Minor W, Herr JC, Endocrinology. 2008 May;149(5):2108-20. Epub 2008 Jan 17. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/18202122 18202122] | ||
[[Category: Mus musculus]] | [[Category: Mus musculus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: Protein binding]] | [[Category: Protein binding]] | ||
[[Category: Rossmann fold]] | [[Category: Rossmann fold]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu May 22 22:26:40 2008'' |
Revision as of 19:26, 22 May 2008
Crystal Structure of Mouse Apolipoprotein A-I Binding Protein
Overview
The physiological changes that sperm undergo in the female reproductive tract rendering them fertilization-competent constitute the phenomenon of capacitation. Cholesterol efflux from the sperm surface and protein kinase A (PKA)-dependent phosphorylation play major regulatory roles in capacitation, but the link between these two phenomena is unknown. We report that apolipoprotein A-I binding protein (AI-BP) is phosphorylated downstream to PKA activation, localizes to both sperm head and tail domains, and is released from the sperm into the media during in vitro capacitation. AI-BP interacts with apolipoprotein A-I, the component of high-density lipoprotein involved in cholesterol transport. The crystal structure demonstrates that the subunit of the AI-BP homodimer has a Rossmann-like fold. The protein surface has a large two compartment cavity lined with conserved residues. This cavity is likely to constitute an active site, suggesting that AI-BP functions as an enzyme. The presence of AI-BP in sperm, its phosphorylation by PKA, and its release during capacitation suggest that AI-BP plays an important role in capacitation possibly providing a link between protein phosphorylation and cholesterol efflux.
About this Structure
2O8N is a Single protein structure of sequence from Mus musculus. Full crystallographic information is available from OCA.
Reference
Biochemical and structural characterization of apolipoprotein A-I binding protein, a novel phosphoprotein with a potential role in sperm capacitation., Jha KN, Shumilin IA, Digilio LC, Chertihin O, Zheng H, Schmitz G, Visconti PE, Flickinger CJ, Minor W, Herr JC, Endocrinology. 2008 May;149(5):2108-20. Epub 2008 Jan 17. PMID:18202122 Page seeded by OCA on Thu May 22 22:26:40 2008
