Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 3 of 3
Full-Text Articles in Medicine and Health Sciences
Conformational Motions And Ligand-Binding Underlying Gating And Regulation In Ip3r Channel, Guizhen Fan, Mariah R Baker, Lara E Terry, Vikas Arige, Muyuan Chen, Alexander B Seryshev, Matthew L Baker, Steven J Ludtke, David I Yule, Irina I Serysheva
Conformational Motions And Ligand-Binding Underlying Gating And Regulation In Ip3r Channel, Guizhen Fan, Mariah R Baker, Lara E Terry, Vikas Arige, Muyuan Chen, Alexander B Seryshev, Matthew L Baker, Steven J Ludtke, David I Yule, Irina I Serysheva
Journal Articles
Inositol-1,4,5-trisphosphate receptors (IP3Rs) are activated by IP3 and Ca2+ and their gating is regulated by various intracellular messengers that finely tune the channel activity. Here, using single particle cryo-EM analysis we determined 3D structures of the nanodisc-reconstituted IP3R1 channel in two ligand-bound states. These structures provide unprecedented details governing binding of IP3, Ca2+ and ATP, revealing conformational changes that couple ligand-binding to channel opening. Using a deep-learning approach and 3D variability analysis we extracted molecular motions of the key protein domains from cryo-EM density data. We find that IP3 binding relies upon intrinsic flexibility of the ARM2 domain in the …
Capture At The Er-Mitochondrial Contacts Licenses Ip, Máté Katona, Ádám Bartók, Zuzana Nichtova, György Csordás, Elena Berezhnaya, David Weaver, Arijita Ghosh, Péter Várnai, David I. Yule, György Hajnóczky
Capture At The Er-Mitochondrial Contacts Licenses Ip, Máté Katona, Ádám Bartók, Zuzana Nichtova, György Csordás, Elena Berezhnaya, David Weaver, Arijita Ghosh, Péter Várnai, David I. Yule, György Hajnóczky
Department of Pathology, Anatomy, and Cell Biology Faculty Papers
Endoplasmic reticulum-mitochondria contacts (ERMCs) are restructured in response to changes in cell state. While this restructuring has been implicated as a cause or consequence of pathology in numerous systems, the underlying molecular dynamics are poorly understood. Here, we show means to visualize the capture of motile IP3 receptors (IP3Rs) at ERMCs and document the immediate consequences for calcium signaling and metabolism. IP3Rs are of particular interest because their presence provides a scaffold for ERMCs that mediate local calcium signaling, and their function outside of ERMCs depends on their motility. Unexpectedly, in a cell model with little ERMC Ca2+ coupling, IP3Rs …
Functional Determination Of Calcium-Binding Sites Required For The Activation Of Inositol 1,4,5-Trisphosphate Receptors, Vikas Arige, Lara E Terry, Larry E Wagner, Sundeep Malik, Mariah R Baker, Guizhen Fan, Suresh K Joseph, Irina I Serysheva, David I Yule
Functional Determination Of Calcium-Binding Sites Required For The Activation Of Inositol 1,4,5-Trisphosphate Receptors, Vikas Arige, Lara E Terry, Larry E Wagner, Sundeep Malik, Mariah R Baker, Guizhen Fan, Suresh K Joseph, Irina I Serysheva, David I Yule
Journal Articles
Inositol 1,4,5-trisphosphate receptors (IP3Rs) initiate a diverse array of physiological responses by carefully orchestrating intracellular calcium (Ca2+) signals in response to various external cues. Notably, IP3R channel activity is determined by several obligatory factors, including IP3, Ca2+, and ATP. The critical basic amino acid residues in the N-terminal IP3-binding core (IBC) region that facilitate IP3 binding are well characterized. In contrast, the residues conferring regulation by Ca2+ have yet to be ascertained. Using comparative structural analysis of Ca2+-binding sites identified in two main families of intracellular Ca2+-release channels, ryanodine receptors (RyRs) and IP3Rs, we identified putative acidic residues coordinating Ca2+ …