The ceroid lipofuscinoses are a group of neurodegenerative lysosomal storage diseases of children and animals that are recessively inherited. In diseased individuals fluorescent storage bodies accumulate in a wide variety of cells, including neurons. Previous studies of these bodies isolated from tissues of affected sheep confirmed that the storage occurs in lysosomes, and showed that the storage body is mostly made of a single protein with an apparent molecular mass of 3500 Da with an N-terminal amino acid sequence that is the same as residues 1-40 of the c-subunit (or dicyclohexylcarbodi-imide-reactive proteolipid) of mitochondrial ATP synthase. In the present work we have shown by direct analysis that the stored protein is identical in sequence with the entire c-subunit of mitochondrial ATP synthase, a very hydrophobic protein of 75 amino acid residues. As far as can be detected by the Edman degradation, the stored protein appears not to have been subject to any post-translational modification other than the correct removal of the mitochondrial import sequences that have been shown in other experiments to be present at the N-terminal of its two different precursors. No other protein accumulates in the storage bodies to any significant extent. Taken with studies of the cDNAs for the c-subunit in normal and diseased sheep, these results indicate that the material that is stored in lysosomes of diseased animals has probably entered mitochondria and has been subjected to the proteolytic processing that is associated with mitochondrial import. This implies that the defect that leads to the lysosomal accumulation concerns the degradative pathway of the c-subunit of ATP synthase. An alternative, but less likely, hypothesis is that for some unknown reason the precursors of subunit c are being directly mis-targeted to lysosomes, where they become processed to yield a protein identical with the protein that is normally found in the mitochondrial ATP synthase assembly, and which then accumulates.

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The Dufour's gland of Anthophora abrupta, a solitary bee, secretes a complex mixture of liquid triglycerides containing one long-chain and two shortchain fatty acids. This is applied inside the earthen brood cells and added to the provision, where it is converted, perhaps by enzymes from the bee's saliva or gut, to solid diglycerides that are later eaten by the bee larvae. This use of Dufour's gland secretion as food and its nutritive function are reminiscent of the royal jelly secreted by honey bees.

LITERATURE CITED Aldrich Library of Infrared Spectra, 3rd ed. Pouchent, C. J., Ed.; Aldrich: Milwaukee, WI, 1981; p 1242D. Alpert, N. L.; Keiser, W. E.; Szymanski, H. A. IR-Theory and Practice of Infrared Spectroscopy; Plenum: New York, 1973; Bourne, S.; Reedy, G. T.; Coffey, P. J.; Mattson, D. Matrix Isolation GC/FTIR. Am. Lab. 1984, 16, 90-95. Christensen, B. W.; Kjaer, A.; Madsen, J. 0.; Olsen, C. E.; Olsen, 0.; Sorensen, H. Mass Spectrometric Characteristics of Some Pertrimethylsilyl Desulfoglucosinolates. Tetrahedron 1982, 38, 353-357. Ettlinger, M. A,; Lundeen, A. J. First Synthesis of a Mustard Oil Glucoside; The Enzymatic Lossen Rearrangement.A new, general-purpose analytical procedure for identification of desulfoglucosinolates from Brassica vegetables has been developed by combining high-performance capillary gas chromatography (HPCGC) with positive-ion chemical ionization mass spectrometry (PICIMS) and PICIMS/MS. HPCGC on a 25 m X 0.2 mm Ultra 1 WCOT fused silica column gave highly reproducible base-line separation of alkyl, alkenyl, hydroxyalkenyl, aryl, and indole desulfoglucosinolates as their per(trimethylsily1)desulfoglucosinolate analogues. PICIMS and PICIMS/MS of these compounds using methane as the reagent gas gave conventional and daughter ion mass spectra in which the major ions were highly diagnostic of the glucosinolate structure.