Tracking Ca2+ ATPase intermediates in real time by x-ray solution scattering

Pedersen, Martin Nors (author)

Eklund, Mattias (author)

Sitsel, Aljona (author)

Li, Chenge (author): Stockholms universitet,Institutionen för biokemi och biofysik

Duelli, Annette (author)

Levantino, Matteo (author)

Wulff, Michael (author)

Barth, Andreas (author): Stockholms universitet,Institutionen för biokemi och biofysik

Olesen, Claus (author)

Nissen, Poul (author)

(creator_code:org_t)

American Association for the Advancement of Science, 2020
2020
English.
In: Science Advances. - : American Association for the Advancement of Science. - 2375-2548. ; 6:12

Related links:: https://doi.org/10.1...; show more...; https://umu.diva-por... (primary) (Raw object); https://www.science....; https://urn.kb.se/re...; https://doi.org/10.1...; https://urn.kb.se/re...; show less...

Abstract Subject headings

Sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) transporters regulate calcium signaling by active calcium ion reuptake to internal stores. Structural transitions associated with transport have been characterized by x-ray crystallography, but critical intermediates involved in the accessibility switch across the membrane are missing. We combined time-resolved x-ray solution scattering (TR-XSS) experiments and molecular dynamics (MD) simulations for real-time tracking of concerted SERCA reaction cycle dynamics in the native membrane. The equilibrium [Ca-2] E1 state before laser activation differed in the domain arrangement compared with crystal structures, and following laser-induced release of caged ATP, a 1.5-ms intermediate was formed that showed closure of the cytoplasmic domains typical of E1 states with bound Ca2+ and ATP. A subsequent 13-ms transient state showed a previously unresolved actuator (A) domain arrangement that exposed the ADP-binding site after phosphorylation. Hence, the obtained TR-XSS models determine the relative timing of so-far elusive domain rearrangements in a native environment.

By the author/editor: Ravishankar, Har ...; Pedersen, Martin ...; Eklund, Mattias; Sitsel, Aljona; Li, Chenge; Duelli, Annette; show more...; Levantino, Matte ...; Wulff, Michael; Barth, Andreas; Olesen, Claus; Nissen, Poul; Andersson, Magnu ...; show less...

About the subject

NATURAL SCIENCES: NATURAL SCIENCES; and Physical Science ...; and Atom and Molecul ...

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.