Glycophylogenetic Aspects of Lower Animals

Biochemical studies on sphingolipids of Artemia franciscana: novel neutral glycosphingolipids

“…Both CTSes are elongated from MacCer as the common substrate by the two enzymes involved, ␤ 3-N -acetylglucosaminyltransferase and ␣ 3-fucosyltransferase (see Scheme 1 ), and both CTSes independently elongate a saccharide to synthesize each series of CTeS. Interestingly, not only nAtCTeS but also At 4 Cer were abundant as CTeS in the brine shrimp Artemia franciscana , despite the fact that there is no report that has detected At 4 Cer to be abundant except for reports of fl ies' GSLs ( 5,7,8,33 ). It has been shown in Arthropoda that the nonarthro-series sugar chain was dominant in a cultured insect cell line, namely High-Five cells ( 31 ).…”

“…Structural analyses of neutral GSLs with some sugar residues have been performed in several Arthropodae: the green-bottle fl y Lucilia caesar ( 7 ) and the blowfl y Calliphora vicina ( 8 ), existence of a Gal ␤ 3Man ␤ 4Glc ␤ 1Cer core pathway is not suffi cient to rescue the brn mutation, the observation that brn is essential for development does not rule out the existence of one or more alternative glycosylation pathways operating during the life cycle of a normal fl y. It was also indicated that more complex GSLs such as At 4 Cer and At 5 Cer were necessary for normal development in Drosophila ( 27 ). In the current report on Artemia , we show that AtCTeS was abundant in amount (6.9 mg) whereas AtCTS was minor (2.1 mg), and we propose that the likely source of GSL with more than fi ve sugar residues is the core arthro-series sugar chain, elongated by transfer of the sugars occurring at the terminus of the nonarthro-series, as a branch (see Scheme 1 ).…”

“…GSLs, which are expressed on the outer side of the lipid bilayer in animal cells, form patches with sphingomyelin (microdomains) and play a foundational role in intercellular adhesion, cellular recognition, differentiation/growth, and immune response (1)(2)(3). However, a comprehensive understanding of GSL function has not yet been attained because of the structural complexity in the sugar chain of GSLs even in vertebrates and invertebrates ( 4,5 ). We have analyzed the GSL structures in lower animals on the assumption that their complexity plays an important role in maintaining the biological activity of multicellular organisms.…”

Biochemical studies on sphingolipids of Artemia franciscana: complex neutral glycosphingolipids

“…GSLs are ubiquitous on the outer surface of the plasma membrane in animal cells, aggregated into patches called microdomains, and play an essential role in intercellular interaction and recognition [1–3]. However, a comprehensive understanding of GSL function has not yet been attained because of the structural complexity of the sugar chain and ceramide moiety [4, 5]. …”

“…Functional analyses of GSLs by knockout experiments of egghead and brainiac have shown that At 3 Cer is essential for insect development [8]. Furthermore, At 3 Cer was detected in flies, including Lucilia caesar and Calliphora vicina , as well as in arthropods (the millipede Parafontaria laminata armigera ) and crustaceans ( Euphausia superba , Macrobrachium nipponense ) [5]. We have further demonstrated the existence of At 3 Cer and some shorter GSLs, including GlcCer (CMS), mactosylceramide (MacCer, CDS), II 3 Fucα-MacCer (nonarthro-CTS), At 4 Cer (CTeS), II 3 (GlcNAcα2Fucα)-MacCer (nonarthro-CTeS), III 3 Fucα-At 4 Cer (CPS), and III 3 (GlcNAcα2Fucα)-At 4 Cer (CHS), in cysts of the brine shrimp Artemia franciscana [9].…”