Cell-specific deletion of glucosylceramide synthase in brain leads to severe neural defects after birth.
Sialic acid-containing glycosphingolipids, i.e., gangliosides, constitute a major component of neuronal cells and are thought to be essential for brain function. UDP-glucose:ceramide glucosyltransferase (Ugcg) catalyzes the initial step of glycosphingolipid (GSL) biosynthesis. To gain insight into the role of GSLs in brain development and function, a cell-specific disruption of Ugcg was performed as indicated by the absence of virtually all glucosylceramide-based GSLs. Shortly after birth, mice showed dysfunction of cerebellum and peripheral nerves, associated with structural defects. Axon branching of Purkinje cells was significantly reduced. In primary cultures of neurons, dendritic complexity was clearly diminished, and pruning occurred early. Myelin sheaths of peripheral nerves were broadened and focally severely disorganized. GSL deficiency also led to a down-regulation of gene expression sets involved in brain development and homeostasis. Mice died approximately 3 weeks after birth. These results imply that GSLs are essential for brain maturation.
Jennemann
Richard
R
Abteilungen Zelluläre und Molekulare Pathologie, Deutsches Krebsforschungszentrum Heidelberg, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany. r.jennemann@dkfz.de
Sandhoff
Roger
R
Wang
Shijun
S
Kiss
Eva
E
Gretz
Norbert
N
Zuliani
Cecilia
C
Martin-Villalba
Ana
A
Jäger
Richard
R
Schorle
Hubert
H
Kenzelmann
Marc
M
Bonrouhi
Mahnaz
M
Wiegandt
Herbert
H
Gröne
Hermann-Josef
HJ
D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000201:enzymology* / Q000473:pathology* / Q000503:physiopathology; D005260:Female; D018390:Gene Targeting; D005964:Glucosyltransferases / Q000172:deficiency* / Q000235:genetics; D006028:Glycosphingolipids / Q000096:biosynthesis; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009410:Nerve Degeneration / Q000201:enzymology / Q000473:pathology; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
D006028:Glycosphingolipids; D012333:RNA, Messenger; D005964:Glucosyltransferases; C023246:ceramide glucosyltransferase