Deciphering the molecular mechanism responsible for GCaMP6m's Ca2+-dependent change in fluorescence.
The goal of this work is to determine how GCaMP6m's fluorescence is altered in response to Ca2+-binding. Our detailed spectroscopic study reveals the simplest explanation for how GCaMP6m changes fluorescence in response to Ca2+ is with a four-state model, in which a Ca2+-dependent change of the...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2017-01-01
|
| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC5300113?pdf=render |
| _version_ | 1818382315413307392 |
|---|---|
| author | Lauren M Barnett Thomas E Hughes Mikhail Drobizhev |
| author_facet | Lauren M Barnett Thomas E Hughes Mikhail Drobizhev |
| author_sort | Lauren M Barnett |
| collection | DOAJ |
| description | The goal of this work is to determine how GCaMP6m's fluorescence is altered in response to Ca2+-binding. Our detailed spectroscopic study reveals the simplest explanation for how GCaMP6m changes fluorescence in response to Ca2+ is with a four-state model, in which a Ca2+-dependent change of the chromophore protonation state, due to a shift in pKa, is the predominant factor. The pKa shift is quantitatively explained by a change in electrostatic potential around the chromophore due to the conformational changes that occur in the protein when calmodulin binds Ca2+ and interacts with the M13 peptide. The absolute pKa values for the Ca2+-free and Ca2+-saturated states of GCaMP6m are critical to its high signal-to-noise ratio. This mechanism has important implications for further improvements to GCaMP6m and potentially for other similarly designed biosensors. |
| first_indexed | 2024-12-14T02:48:31Z |
| format | Article |
| id | doaj.art-3e77e6f6b2fb478f89f621207d6b3fce |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-14T02:48:31Z |
| publishDate | 2017-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-3e77e6f6b2fb478f89f621207d6b3fce2022-12-21T23:19:49ZengPublic Library of Science (PLoS)PLoS ONE1932-62032017-01-01122e017093410.1371/journal.pone.0170934Deciphering the molecular mechanism responsible for GCaMP6m's Ca2+-dependent change in fluorescence.Lauren M BarnettThomas E HughesMikhail DrobizhevThe goal of this work is to determine how GCaMP6m's fluorescence is altered in response to Ca2+-binding. Our detailed spectroscopic study reveals the simplest explanation for how GCaMP6m changes fluorescence in response to Ca2+ is with a four-state model, in which a Ca2+-dependent change of the chromophore protonation state, due to a shift in pKa, is the predominant factor. The pKa shift is quantitatively explained by a change in electrostatic potential around the chromophore due to the conformational changes that occur in the protein when calmodulin binds Ca2+ and interacts with the M13 peptide. The absolute pKa values for the Ca2+-free and Ca2+-saturated states of GCaMP6m are critical to its high signal-to-noise ratio. This mechanism has important implications for further improvements to GCaMP6m and potentially for other similarly designed biosensors.http://europepmc.org/articles/PMC5300113?pdf=render |
| spellingShingle | Lauren M Barnett Thomas E Hughes Mikhail Drobizhev Deciphering the molecular mechanism responsible for GCaMP6m's Ca2+-dependent change in fluorescence. PLoS ONE |
| title | Deciphering the molecular mechanism responsible for GCaMP6m's Ca2+-dependent change in fluorescence. |
| title_full | Deciphering the molecular mechanism responsible for GCaMP6m's Ca2+-dependent change in fluorescence. |
| title_fullStr | Deciphering the molecular mechanism responsible for GCaMP6m's Ca2+-dependent change in fluorescence. |
| title_full_unstemmed | Deciphering the molecular mechanism responsible for GCaMP6m's Ca2+-dependent change in fluorescence. |
| title_short | Deciphering the molecular mechanism responsible for GCaMP6m's Ca2+-dependent change in fluorescence. |
| title_sort | deciphering the molecular mechanism responsible for gcamp6m s ca2 dependent change in fluorescence |
| url | http://europepmc.org/articles/PMC5300113?pdf=render |
| work_keys_str_mv | AT laurenmbarnett decipheringthemolecularmechanismresponsibleforgcamp6msca2dependentchangeinfluorescence AT thomasehughes decipheringthemolecularmechanismresponsibleforgcamp6msca2dependentchangeinfluorescence AT mikhaildrobizhev decipheringthemolecularmechanismresponsibleforgcamp6msca2dependentchangeinfluorescence |