Recent development in mammalian sialidase molecular biology.
This review summarizes the recent research development on mammalian sialidase molecular cloning. Sialic acid-containing compounds are involved in several physiological processes, and sialidases, as glycohydrolytic enzymes that remove sialic acid residues, play a pivotal role as well. Sialidases hydrolyze the nonreducing, terminal sialic acid linkage in various natural substrates, such as glycoproteins, glycolipids, gangliosides, and polysaccharides. Mammalian sialidases are present in several tissues/organs and cells with a typical subcellular distribution: they are the lysosomal, the cytosolic, and the plasma membrane-associated sialidases. Starting in 1993, 12 different mammalian sialidases have been cloned and sequenced. A comparison of their amino acid sequences revealed the presence of highly conserved regions. These conserved regions are shared with viral and microbial sialidases that have been characterized at three-dimensional structural level, allowing us to perform the molecular modeling of the mammalian proteins and suggesting a monophyletic origin of the sialidase enzymes. Overall, the availability of the cDNA species encoding mammalian sialidases is an important step leading toward a comprehensive picture of the relationships between the structure and biological function of these enzymes.
Monti
Eugenio
E
Department of Biomedical Sciences and Biotechnology, University of Brescia, Italy. monti@med.unibs.it
Preti
Augusto
A
Venerando
Bruno
B
Borsani
Giuseppe
G
D000595:Amino Acid Sequence; D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D002462:Cell Membrane / Q000201:enzymology; D003001:Cloning, Molecular; D006801:Humans; D008322:Mammals; D008969:Molecular Sequence Data; D009081:Mucolipidoses / Q000201:enzymology; D016297:Mutagenesis, Site-Directed; D009369:Neoplasms / Q000201:enzymology; D009439:Neuraminidase / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D017386:Sequence Homology, Amino Acid; D014162:Transfection
D009439:Neuraminidase