title: Overexpression of Galnt3 in chondrocytes resulted in dwarfism due to the increase of mucin-type O-glycans and reduction of glycosaminoglycans.
abstract: Galnt3, UDP-N-acetyl-α-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase 3, transfers N-acetyl-D-galactosamine to serine and threonine residues, initiating mucin type O-glycosylation of proteins. We searched the target genes of Runx2, which is an essential transcription factor for chondrocyte maturation, in chondrocytes and found that Galnt3 expression was up-regulated by Runx2 and severely reduced in Runx2(-/-) cartilaginous skeletons. To investigate the function of Galnt3 in chondrocytes, we generated Galnt3(-/-) mice and chondrocyte-specific Galnt3 transgenic mice under the control of the Col2a1 promoter-enhancer. Galnt3(-/-) mice showed a delay in endochondral ossification and shortened limbs at embryonic day 16.5, suggesting that Galnt3 is involved in chondrocyte maturation. Galnt3 transgenic mice presented dwarfism, the chondrocyte maturation was retarded, the cell cycle in chondrocytes was accelerated, premature chondrocyte apoptosis occurred, and the growth plates were disorganized. The binding of Vicia villosa agglutinin, which recognizes the Tn antigen (GalNAc-O-Ser/Thr), was drastically increased in chondrocytes, and aggrecan (Acan) was highly enriched with Tn antigen. However, safranin O staining, which recognizes glycosaminoglycans (GAGs), and Acan were severely reduced. Chondroitin sulfate was reduced in amount, but the elongation of chondroitin sulfate chains had not been severely disturbed in the isolated GAGs. These findings indicate that overexpression of Galnt3 in chondrocytes caused dwarfism due to the increase of mucin-type O-glycans and the reduction of GAGs, probably through competition with xylosyltransferases, which initiate GAG chains by attaching O-linked xylose to serine residues, suggesting a negative effect of Galnt family proteins on Acan deposition in addition to the positive effect of Galnt3 on chondrocyte maturation.
authors.affiliation: Department of Cell Biology, Unit of Basic Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Carolina Andrea
authors.initials: CA
authors.lastname: Yoshida
authors.affiliation: Department of Cell Biology, Unit of Basic Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kawane
authors.affiliation: Department of Cell Biology, Unit of Basic Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Moriishi
authors.affiliation: Department of Biochemistry, Kobe Pharmaceutical University, Kobe 658-0003, Japan.
authors.forename: Anurag
authors.initials: A
authors.lastname: Purushothaman
authors.affiliation: Department of Cell Biology, Unit of Basic Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Miyazaki
authors.affiliation: Department of Cell Biology, Unit of Basic Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Hisato
authors.initials: H
authors.lastname: Komori
authors.affiliation: Department of Cell Biology, Unit of Basic Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Masako
authors.initials: M
authors.lastname: Mori
authors.affiliation: Department of Cell Biology, Unit of Basic Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Xin
authors.initials: X
authors.lastname: Qin
authors.affiliation: Department of Cell Biology, Unit of Basic Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan,; Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Hashimoto
authors.affiliation: Department of Biochemistry, Kobe Pharmaceutical University, Kobe 658-0003, Japan,; Proteoglycan Signaling and Therapeutics Research Group, Faculty of Advanced Life Science, Hokkaido University Graduate School of Life Science, Frontier Research Center for Post-Genomic Science and Technology, Sapporo 001-0021, Japan, and.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Sugahara
authors.affiliation: Teijin Institute for Biomedical Research, Teijin Ltd., Hino, Tokyo 191-8512, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Yamana
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Takada
authors.affiliation: Department of Cell Biology, Unit of Basic Medical Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan,. Electronic address: komorit@nagasaki-u.ac.jp.
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Komori
mesh_terms: D053674:Aggrecans / Q000235:genetics / Q000378:metabolism; D000818:Animals; D017209:Apoptosis; D002356:Cartilage / Q000378:metabolism / Q000473:pathology; D049109:Cell Proliferation; D002478:Cells, Cultured; D019902:Chondrocytes / Q000378:metabolism*; D002809:Chondroitin Sulfates / Q000378:metabolism*; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics / Q000378:metabolism; D004392:Dwarfism / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D006031:Glycosylation; D006132:Growth Plate / Q000378:metabolism / Q000473:pathology; D008297:Male; D057507:Mice, 129 Strain; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D017350:N-Acetylgalactosaminyltransferases / Q000235:genetics / Q000378:metabolism*; D010012:Osteogenesis; D011499:Protein Processing, Post-Translational; D000097763:Polypeptide N-acetylgalactosaminyltransferase
chemical_list: D053674:Aggrecans; D002809:Chondroitin Sulfates; D050659:Core Binding Factor Alpha 1 Subunit; D017350:N-Acetylgalactosaminyltransferases; D000097763:Polypeptide N-acetylgalactosaminyltransferase; C508320:Acan protein, mouse; C493716:Runx2 protein, mouse
keywords: Aggrecan; Chondrocyte; Galnt3; Glycosaminoglycan; Glycosyltransferase; Mucin; Mucin-type O-Glycan; Proteoglycan
references.citation: Trends Cell Biol. 2006 Sep;16(9):467-76
references.pmid: 16904320
references.citation: J Biol Chem. 2002 Jan 25;277(4):2657-65
references.pmid: 11714693
references.citation: Exp Cell Res. 2002 Feb 15;273(2):178-86
references.pmid: 11822873
references.citation: Endocrinology. 2009 Jun;150(6):2543-50
references.pmid: 19213845
references.citation: J Biol Chem. 1996 Feb 23;271(8):4298-303
references.pmid: 8626777
references.citation: J Biol Chem. 2011 Feb 18;286(7):5803-12
references.pmid: 21148564
references.citation: Development. 2009 May;136(10):1697-706
references.pmid: 19369399
references.citation: Biochem J. 2001 Feb 15;354(Pt 1):199-207
references.pmid: 11171095
references.citation: J Cell Sci. 2011 Oct 15;124(Pt 20):3428-40
references.pmid: 21984813
references.citation: J Bone Miner Res. 2007 Feb;22(2):235-42
references.pmid: 17129170
references.citation: J Cell Biol. 2001 Apr 2;153(1):87-100
references.pmid: 11285276
references.citation: J Biol Chem. 2003 Jun 27;278(26):23971-7
references.pmid: 12697767
references.citation: Histochem Cell Biol. 2013 Feb;139(2):339-54
references.pmid: 23052838
references.citation: Curr Top Dev Biol. 2010;90:291-317
references.pmid: 20691853
references.citation: J Cell Sci. 1995 Dec;108 ( Pt 12):3677-84
references.pmid: 8719874
references.citation: Biochem Biophys Res Commun. 2008 Jul 11;371(4):698-701
references.pmid: 18455506
references.citation: Biochemistry. 2010 Jul 6;49(26):5524-32
references.pmid: 20507176
references.citation: Biochim Biophys Acta. 2002 Dec 19;1573(3):394-405
references.pmid: 12417424
references.citation: Cancer Res. 2011 Dec 1;71(23):7270-9
references.pmid: 21990321
references.citation: Glycobiology. 2003 Jul;13(7):549-57
references.pmid: 12651884
references.citation: Nat Genet. 2004 Jun;36(6):579-81
references.pmid: 15133511
references.citation: Histochemistry. 1985;83(4):303-6
references.pmid: 3934113
references.citation: Glycobiology. 2012 Jun;22(6):736-56
references.pmid: 22183981
references.citation: Biochim Biophys Acta. 2012 Dec;1820(12):2079-94
references.pmid: 23022508
references.citation: Dev Dyn. 1999 Apr;214(4):279-90
references.pmid: 10213384
references.citation: Bioessays. 2003 Jan;25(1):66-71
references.pmid: 12508284
references.citation: Dev Dyn. 1997 Aug;209(4):377-86
references.pmid: 9264261
references.citation: Biochem Soc Trans. 2007 Nov;35(Pt 5):1372-4
references.pmid: 17956354
references.citation: Biochem J. 1996 Jun 1;316 ( Pt 2):487-95
references.pmid: 8687392
references.citation: J Biol Chem. 2001 Jun 22;276(25):22200-8
references.pmid: 11294842
references.citation: J Biol Chem. 2002 Mar 1;277(9):6858-63
references.pmid: 11878264
references.citation: J Biol Chem. 1980 Jul 10;255(13):6084-91
references.pmid: 7391006
references.citation: Int J Exp Pathol. 2009 Dec;90(6):575-86
references.pmid: 19958398
references.citation: J Biol Chem. 2006 Jul 7;281(27):18370-7
references.pmid: 16638743
references.citation: Eur J Endocrinol. 2008 Jun;158(6):929-34
references.pmid: 18322299
references.citation: J Cell Sci. 2004 Jan 26;117(Pt 3):417-25
references.pmid: 14702386
references.citation: FASEB J. 1997 Mar;11(4):227-33
references.pmid: 9068611
references.citation: Genes Dev. 1999 Aug 15;13(16):2072-86
references.pmid: 10465785
references.citation: Glycobiology. 2002 Apr;12(4):57R-68R
references.pmid: 12042245
references.citation: Adv Exp Med Biol. 1988;228:819-47
references.pmid: 3051928
references.citation: Curr Pharm Des. 2009;15(12):1334-48
references.pmid: 19355972
references.citation: J Clin Endocrinol Metab. 2007 May;92(5):1943-7
references.pmid: 17311862
references.citation: Cell. 1997 May 30;89(5):755-64
references.pmid: 9182763
references.citation: Mech Dev. 1999 Feb;80(2):159-70
references.pmid: 10072783
references.citation: Chem Biol Drug Des. 2008 Dec;72(6):455-82
references.pmid: 19090915
references.citation: Oncogene. 2011 Dec 8;30(49):4843-54
references.pmid: 21625220
references.citation: Science. 1996 Aug 2;273(5275):613-22
references.pmid: 8662546
references.citation: Biochem J. 1993 Oct 1;295 ( Pt 1):131-40
references.pmid: 8216207