Article (Scientific journals)
Calreticulin mutants as oncogenic rogue chaperones for TpoR and traffic-defective pathogenic TpoR mutants.
Pecquet, Christian; Chachoua, Ilyas; Roy, Anita et al.
2019In Blood, 133 (25), p. 2669-2681
Peer Reviewed verified by ORBi
 

Files


Full Text
Pecquet et al Blood 2019.pdf
Publisher postprint (2.08 MB)
Download

All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
Animals; Calreticulin/genetics/metabolism; Hematologic Neoplasms/genetics/metabolism; Humans; Mice; Molecular Chaperones/genetics/metabolism; Mutation; Protein Transport/physiology; Receptors, Thrombopoietin/metabolism
Abstract :
[en] Calreticulin (CALR) +1 frameshift mutations in exon 9 are prevalent in myeloproliferative neoplasms. Mutant CALRs possess a new C-terminal sequence rich in positively charged amino acids, leading to activation of the thrombopoietin receptor (TpoR/MPL). We show that the new sequence endows the mutant CALR with rogue chaperone activity, stabilizing a dimeric state and transporting TpoR and mutants thereof to the cell surface in states that would not pass quality control; this function is absolutely required for oncogenic transformation. Mutant CALRs determine traffic via the secretory pathway of partially immature TpoR, as they protect N117-linked glycans from further processing in the Golgi apparatus. A number of engineered or disease-associated TpoRs such as TpoR/MPL R102P, which causes congenital thrombocytopenia, are rescued for traffic and function by mutant CALRs, which can also overcome endoplasmic reticulum retention signals on TpoR. In addition to requiring N-glycosylation of TpoR, mutant CALRs require a hydrophobic patch located in the extracellular domain of TpoR to induce TpoR thermal stability and initial intracellular activation, whereas full activation requires cell surface localization of TpoR. Thus, mutant CALRs are rogue chaperones for TpoR and traffic-defective TpoR mutants, a function required for the oncogenic effects.
Disciplines :
Hematology
Author, co-author :
Pecquet, Christian
Chachoua, Ilyas
Roy, Anita
Balligand, Thomas
VERTENOEIL, Gaëlle ;  Centre Hospitalier Universitaire de Liège - CHU > Département de médecine interne > Service d'hématologie clinique
Leroy, Emilie
Albu, Roxana-Irina
Defour, Jean-Philippe
Nivarthi, Harini
Hug, Eva
Xu, Erica
Ould-Amer, Yasmine
Mouton, Céline
Colau, Didier
Vertommen, Didier
Shwe, Myat Marlar
Marty, Caroline
Plo, Isabelle
Vainchenker, William
Kralovics, Robert
Constantinescu, Stefan N.
More authors (11 more) Less
Language :
English
Title :
Calreticulin mutants as oncogenic rogue chaperones for TpoR and traffic-defective pathogenic TpoR mutants.
Publication date :
2019
Journal title :
Blood
ISSN :
0006-4971
eISSN :
1528-0020
Publisher :
American Society of Hematology, Washington, United States - District of Columbia
Volume :
133
Issue :
25
Pages :
2669-2681
Peer reviewed :
Peer Reviewed verified by ORBi
Commentary :
© 2019 by The American Society of Hematology.
Available on ORBi :
since 24 November 2020

Statistics


Number of views
62 (2 by ULiège)
Number of downloads
86 (3 by ULiège)

Scopus citations®
 
70
Scopus citations®
without self-citations
53
OpenCitations
 
60

Bibliography


Similar publications



Contact ORBi