The origin and function of platelet glycosyltransferases. Blood 2012 Jul 19;120(3):626-35
Date
05/23/2012Pubmed ID
22613794Pubmed Central ID
PMC3401214DOI
10.1182/blood-2012-02-409235Scopus ID
2-s2.0-84864127482 (requires institutional sign-in at Scopus site) 80 CitationsAbstract
Platelets are megakaryocyte subfragments that participate in hemostatic and host defense reactions and deliver pro- and antiangiogenic factors throughout the vascular system. Although they are anucleated cells that lack a complex secretory apparatus with distinct Golgi/endoplasmic reticulum compartments, past studies have shown that platelets have glycosyltransferase activities. In the present study, we show that members of 3 distinct glycosyltransferase families are found within and on the surface of platelets. Immunocytology and flow cytometry results indicated that megakaryocytes package these Golgi-derived glycosyltransferases into vesicles that are sent via proplatelets to nascent platelets, where they accumulate. These glycosyltransferases are active, and intact platelets glycosylate large exogenous substrates. Furthermore, we show that activation of platelets results in the release of soluble glycosyltransferase activities and that platelets contain sufficient levels of sugar nucleotides for detection of glycosylation of exogenously added substrates. Therefore, the results of the present study show that blood platelets are a rich source of both glycosyltransferases and donor sugar substrates that can be released to function in the extracellular space. This platelet-glycosylation machinery offers a pathway to a simple glycoengineering strategy improving storage of platelets and may serve hitherto unknown biologic functions.
Author List
Wandall HH, Rumjantseva V, Sørensen AL, Patel-Hett S, Josefsson EC, Bennett EP, Italiano JE Jr, Clausen H, Hartwig JH, Hoffmeister KMAuthor
Karin Hoffmeister MD Professor in the Biochemistry department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsBlood Platelets
Galactosyltransferases
Glycosylation
Glycosyltransferases
Golgi Apparatus
Humans
Male
Megakaryocytes
Mice
Mice, Inbred C57BL
Mice, Knockout
Multigene Family
N-Acetylgalactosaminyltransferases
N-Acetylneuraminic Acid
Platelet-Rich Plasma
Sialyltransferases
Substrate Specificity
