PXD042396

PXD042396 is an original dataset announced via ProteomeXchange.

Title	Initiation of B-type starch granules in wheat endosperm requires the plastidial α-glucan phosphorylase PHS1.
Description	PHS1 is a plastidial α-glucan phosphorylase that can elongate and degrade maltooligosaccharides (MOS), but its exact physiological role in plants is poorly understood. Here, we discover a specialised role of PHS1 in establishing the unique bimodal characteristic of starch granules in the wheat endosperm. Wheat endosperm contains large A-type granules that initiate at early grain development, and small B-type granules that initiate in later grain development. We demonstrate that PHS1 interacts with BGC1 – a carbohydrate-binding protein essential for normal B-type granule initiation. Mutants of tetraploid durum wheat deficient in all homeologs of PHS1 had normal A-type granules, but fewer and larger B-type granules. Further, using a double mutant defective in both PHS1 and BGC1, we show that PHS1 is exclusively involved in B-type granule initiation. Grain size and starch content were not affected by the mutations. In leaves, the total starch content and number of starch granules per chloroplast were not affected by loss of PHS1, suggesting that its role in granule initiation in wheat is limited to the endosperm. We therefore propose that the initiation of A- and B-type granules occur by distinct biochemical mechanisms, where PHS1 plays an exclusive role in B-type granule initiation.
HostingRepository	PRIDE
AnnounceDate	2024-01-22
AnnouncementXML	Submission_2024-01-22_10:54:10.400.xml
DigitalObjectIdentifier	https://dx.doi.org/10.6019/PXD042396
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Supported dataset by repository
PrimarySubmitter	Gerhard Saalbach
SpeciesList	scientific name: Triticum turgidum; NCBI TaxID: 4571;
ModificationList	monohydroxylated residue; iodoacetamide derivatized residue
Instrument	Orbitrap Eclipse

Revision	Datetime	Status	ChangeLog Entry
0	2023-05-22 07:46:22	ID requested
⏵ 1	2024-01-22 10:54:10	announced

10.6019/PXD042396;

submitter keyword: PHS1/PHO1, BGC1, A- and B-type granules,Wheat

David Seung
contact affiliation	Group Leader Department of Biochemistry and Metabolism John Innes Centre Norwich Research Park Norwich NR4 7UH, UK
contact email	David.Seung@jic.ac.uk
lab head
Gerhard Saalbach
contact affiliation	Biological Chemistry
contact email	gerhard.saalbach@jic.ac.uk
dataset submitter

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PRIDE project URI

• PRIDE
  1. PXD042396
     1. Label: PRIDE project
     2. Name: Initiation of B-type starch granules in wheat endosperm requires the plastidial α-glucan phosphorylase PHS1.