» Articles » PMID: 22649382

Extracellular Domain N-glycosylation Controls Human Thrombopoietin Receptor Cell Surface Levels

Overview
Specialty Endocrinology
Date 2012 Jun 1
PMID 22649382
Citations 12
Authors
Affiliations
Soon will be listed here.
Abstract

The thrombopoietin receptor (TpoR) is a type I transmembrane protein that mediates the signaling functions of thrombopoietin (Tpo) in regulating megakaryocyte differentiation, platelet formation, and hematopoietic stem cell renewal. We probed the role of each of the four extracellular domain putative N-glycosylation sites for cell surface localization and function of the receptor. Single N-glycosylation mutants at any of the four sites were able to acquire the mature N-glycosylated pattern, but exhibited a decreased Tpo-dependent JAK2-STAT response in stably transduced Ba/F3 or Ba/F3-JAK2 cell lines. The ability of JAK2 to promote cell surface localization and stability of TpoR required the first N-glycosylation site (Asn117). In contrast, the third N-glycosylation site (Asn298) decreased receptor maturation and stability. TpoR mutants lacking three N-glycosylation sites were defective in maturation, but N-glycosylation on the single remaining site could be detected by sensitivity to PNGaseF. The TpoR mutant defective in all four N-glycosylation sites was severely impaired in plasma membrane localization and was degraded by the proteasome. N-glycosylation receptor mutants are not misfolded as, once localized on the cell surface in overexpression conditions, they can bind and respond to Tpo. Our data indicate that extracellular domain N-glycosylation sites regulate in a combinatorial manner cell surface localization of TpoR. We discuss how mutations around TpoR N-glycosylation sites might contribute to inefficient receptor traffic and disease.

Citing Articles

Myeloproliferative Neoplasms: Challenging Dogma.

Spivak J J Clin Med. 2024; 13(22).

PMID: 39598101 PMC: 11595126. DOI: 10.3390/jcm13226957.


Effects of calreticulin mutations on cell transformation and immunity.

Desikan H, Kaur A, Pogozheva I, Raghavan M J Cell Mol Med. 2023; 27(8):1032-1044.

PMID: 36916035 PMC: 10098294. DOI: 10.1111/jcmm.17713.


A marine sponge-derived lectin reveals hidden pathway for thrombopoietin receptor activation.

Watari H, Kageyama H, Masubuchi N, Nakajima H, Onodera K, Focia P Nat Commun. 2022; 13(1):7262.

PMID: 36433967 PMC: 9700728. DOI: 10.1038/s41467-022-34921-2.


Mutant CALR's "sweet tooth".

Rao S, Carlson K Blood. 2022; 140(11):1187-1189.

PMID: 36107460 PMC: 9479035. DOI: 10.1182/blood.2022017448.


Whole-genome CRISPR screening identifies N-glycosylation as a genetic and therapeutic vulnerability in CALR-mutant MPNs.

Jutzi J, Marneth A, Ciboddo M, Guerra-Moreno A, Jimenez-Santos M, Kosmidou A Blood. 2022; 140(11):1291-1304.

PMID: 35763665 PMC: 9479036. DOI: 10.1182/blood.2022015629.


References
1.
Tijssen M, Di Summa F, van den Oudenrijn S, Zwaginga J, van der Schoot C, Voermans C . Functional analysis of single amino-acid mutations in the thrombopoietin-receptor Mpl underlying congenital amegakaryocytic thrombocytopenia. Br J Haematol. 2008; 141(6):808-13. DOI: 10.1111/j.1365-2141.2008.07139.x. View

2.
Ballmaier M, Germeshausen M, Schulze H, Cherkaoui K, Lang S, Gaudig A . c-mpl mutations are the cause of congenital amegakaryocytic thrombocytopenia. Blood. 2001; 97(1):139-46. DOI: 10.1182/blood.v97.1.139. View

3.
Drachman J, Kaushansky K . Structure and function of the cytokine receptor superfamily. Curr Opin Hematol. 1995; 2(1):22-8. DOI: 10.1097/00062752-199502010-00004. View

4.
Vigon I, Florindo C, Fichelson S, Guenet J, Mattei M, Souyri M . Characterization of the murine Mpl proto-oncogene, a member of the hematopoietic cytokine receptor family: molecular cloning, chromosomal location and evidence for a function in cell growth. Oncogene. 1993; 8(10):2607-15. View

5.
Dumoutier L, Van Roost E, Colau D, Renauld J . Human interleukin-10-related T cell-derived inducible factor: molecular cloning and functional characterization as an hepatocyte-stimulating factor. Proc Natl Acad Sci U S A. 2000; 97(18):10144-9. PMC: 27764. DOI: 10.1073/pnas.170291697. View