A focused microarray approach to functional glycomics: transcriptional regulation of the glycome.
Glycosylation is the most common posttranslational modification of proteins, yet genes relevant to the synthesis of glycan structures and function are incompletely represented and poorly annotated on the commercially available arrays. To fill the need for expression analysis of such genes, we employed the Affymetrix technology to develop a focused and highly annotated glycogene-chip representing human and murine glycogenes, including glycosyltransferases, nucleotide sugar transporters, glycosidases, proteoglycans, and glycan-binding proteins. In this report, the array has been used to generate glycogene-expression profiles of nine murine tissues. Global analysis with a hierarchical clustering algorithm reveals that expression profiles in immune tissues (thymus [THY], spleen [SPL], lymph node, and bone marrow [BM]) are more closely related, relative to those of nonimmune tissues (kidney [KID], liver [LIV], brain [BRN], and testes [TES]). Of the biosynthetic enzymes, those responsible for synthesis of the core regions of N- and O-linked oligosaccharides are ubiquitously expressed, whereas glycosyltransferases that elaborate terminal structures are expressed in a highly tissue-specific manner, accounting for tissue and ultimately cell-type-specific glycosylation. Comparison of gene expression profiles with matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) profiling of N-linked oligosaccharides suggested that the alpha1-3 fucosyltransferase 9, Fut9, is the enzyme responsible for terminal fucosylation in KID and BRN, a finding validated by analysis of Fut9 knockout mice. Two families of glycan-binding proteins, C-type lectins and Siglecs, are predominately expressed in the immune tissues, consistent with their emerging functions in both innate and acquired immunity. The glycogene chip reported in this study is available to the scientific community through the Consortium for Functional Glycomics (CFG) (http://www.functionalglycomics.org).
Comelli
Elena M
EM
Department of Molecular Biology and Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
Head
Steven R
SR
Gilmartin
Tim
T
Whisenant
Thomas
T
Haslam
Stuart M
SM
North
Simon J
SJ
Wong
Nyet-Kui
NK
Kudo
Takashi
T
Narimatsu
Hisashi
H
Esko
Jeffrey D
JD
Drickamer
Kurt
K
Dell
Anne
A
Paulson
James C
JC
D000818:Animals; D050260:Carbohydrate Metabolism / Q000235:genetics*; D002240:Carbohydrate Sequence; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006023:Glycoproteins / Q000096:biosynthesis* / Q000737:chemistry / Q000378:metabolism; D006031:Glycosylation; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D009928:Organ Specificity; D010802:Phylogeny; D014158:Transcription, Genetic
D006023:Glycoproteins