Article

Seminolipid and its precursor/degradative product, galactosylalkylacylglycerol, in the testis of saposin A- and prosaposin-deficient mice.

Department of Biochemistry, Teikyo University School of Medicine, Kaga 2-11-1, Itabashi-ku, Tokyo 173-8605, Japan.
The Journal of Lipid Research (impact factor: 5.56). 10/2003; 44(9):1737-43. DOI:10.1194/jlr.M300119-JLR200 pp.1737-43
Source: PubMed

ABSTRACT Sphingolipid activator proteins (saposins A, B, C, and D) are derived from a common precursor protein (prosaposin) and specifically activate in vivo degradation of glycolipids with short carbohydrate chains. A mouse model of prosaposin deficiency (prosaposin-/-) closely mimics the human disease with an elevation of multiple glycolipids. The recently developed saposin A-/- mice showed a chronic form of globoid cell leukodystrophy, establishing the essential in vivo role of saposin A as an activator for galactosylceramidase to degrade galactosylceramide. Seminolipid, the principal glycolipid in spermatozoa, and its precursor/degradative product, galactosylalkylacylglycerol (GalEAG), were analyzed in the testis of the two mouse mutants by electrospray ionization mass spectrometry. Saposin A-/- mice showed the normal seminolipid level, while that of prosaposin-/- mice was approximately 150% of the normal level at the terminal stage. In contrast, GalEAG increased up to 10 times in saposin A-/- mice, whereas it decreased with age in the wild-type as well as in prosaposin-/- mice. These analytical findings on the two saposin mutants may shed some light on the physiological function of seminolipid and GalEAG.

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    Karin Gorgas, Andre Teigler, Dorde Komljenovic, Wilhelm W Just
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    Biochimica et Biophysica Acta 01/2007; 1763(12):1511-26. · 4.66 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

chronic form
 
common precursor protein
 
degrade galactosylceramide
 
developed saposin A-/- mice
 
electrospray ionization mass spectrometry
 
globoid cell leukodystrophy
 
human disease
 
multiple glycolipids
 
normal level
 
normal seminolipid level
 
precursor/degradative product
 
principal glycolipid
 
prosaposin-/-
 
prosaposin-/- mice
 
saposin A-/- mice
 
short carbohydrate chains
 
Sphingolipid activator proteins
 
two mouse mutants
 
two saposin mutants
 
vivo degradation
 

Keiko Tadano-Aritomi