Chloroplast PetD protein: evidence for SRP/Alb3-dependent insertion into the thylakoid membrane
Jarosław Króliczewski , Rafał Bartoszewski , Bożena Króliczewska
AbstractBackground: In thylakoid membrane, each monomer of the dimeric complex of cytochrome b6f is comprised of eight subunits that are both nucleus- and plastid-encoded. Proper cytochrome b6f complex integration into the thylakoid membrane requires numerous regulatory factors for coordinated transport, insertion and assembly of the subunits. Although, the chloroplast-encoded cytochrome b6f subunit IV (PetD) consists of three transmembrane helices, the signal and the mechanism of protein integration into the thylakoid membrane have not been identified. Results: Here, we demonstrate that the native PetD subunit cannot incorporate into the thylakoid membranes spontaneously, but that proper integration occurs through the post-translational signal recognition particle (SRP) pathway. Furthermore, we show that PetD insertion into thylakoid membrane involves the coordinated action of cpFTSY, cpSRP54 and ALB3 insertase. Conclusions: PetD subunit integration into the thylakoid membrane is a post-translational and an SRP-dependent process that requires the formation of the cpSRP-cpFtsY-ALB3-PetD complex. This data provides a new insight into the molecular mechanisms by which membrane proteins integration into the thylakoid membrane is accomplished and is not limited to PetD.
|Journal series||BMC Plant Biology, ISSN 1471-2229, (A 40 pkt)|
|Publication size in sheets||0.7|
|Keywords in English||Cytochrome b6f complex; Thylakoid protein import; PetD; cpSECY; cpSRP54; ALB3|
|Internal identifier||64563; TX-5a54747fc2dc3aac90f2c504|
|License||Journal (articles only); published final; ; with publication|
|Score||= 40.0, 07-09-2020, ArticleFromJournal|
|Publication indicators||= 0; = 0; : 2017 = 1.344; : 2017 = 3.93 (2) - 2017=4.381 (5)|
|Citation count*||2 (2020-09-20)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.