Regulatory Changes of N-Acetylgalactosamine
Transcription
Regulatory Changes of N-Acetylgalactosamine
Original Article Regulatory Changes of N-Acetylgalactosamine Terminal Sugar in Early Mouse Embryonic Paraxial Mesenchyme 0RKDPPDG0HKGL+DVVDQ]DGHK7DKHUL3K'1$OL5H]D(EUDKLP]DGHK%LGHVNDQ3K'2 0RKDPPDG5H]D0LUL3K'3* 'HSDUWPHQWRI$QDWRP\6FKRRORI0HGLFLQH%LUMDQG8QLYHUVLW\RI0HGLFDO6FLHQFHV%LUMDQG,UDQ 'HSDUWPHQWRI$QDWRP\6FKRRORI0HGLFLQH0DVKDG8QLYHUVLW\RI0HGLFDO6FLHQFHV0DVKDG,UDQ 6FKRRORI+HDOWK%LUMDQG8QLYHUVLW\RI0HGLFDO6FLHQFHV%LUMDQG,UDQ * Corresponding Address: P.O.Box: 379, School of Health, Birjand University of Medical Sciences, Birjand, Iran Email: Miri_moh2516@yahoo.com 5HFHLYHG$XJ$FFHSWHG-DQ Abstract 2EMHFWLYH The development of vertebrae is a complex phenomenon that is correlated with distinct morphological and biochemical alterations in the paraxial mesenchyme and glycoconjugates. The purpose of this study is to investigate the glycosylation pattern in paraxial mesenchyme-forming vertebrae by using the lectin histochemical technique. 0DWHULDOVDQG0HWKRGV,QWKLVGHVFULSWLYHDQDO\WLFVWXG\%*¿[HGSDUDI¿QVHFWLRQVRI 9 to 15 day Balb/c mouse embryos were processed for histochemical studies using seven GLIIHUHQW+53ODEHOOHGOHFWLQV*O\FLQPD[6%$0DFOXUDSRPLIHUD03$:LVWDULDÀRULEXQGD:)$9LFLDYLOORVD99$ZKLFKDOORIWKHPDUHVSHFL¿FIRU1DFHW\OJDODFWRVDPLQH (GalNAc), 8OH[HXURSLXV8($ELQGVWRĮ/IXFRVHZKHDWJHUPDJJOXWLQLQ:*$ELQGV WRVLDOLFDFLGDQG*ULIIRQLDVLPSOLFLIROLD*6$%ELQGVWRJDODFWRVHWHUPLQDOVXJDUV The sections were observed separately by three examiners who were blinded to the lectins. Grading was done according to the intensity of the tested lectins’ reactions with the VSHFLPHQIURPQHJDWLYHWRVHYHUH'DWDZDVDQDO\VHGZLWK6366VRIWZDUHYHUVLRQDQGWKHQRQSDUDPHWULF.UXVNDO:DOOLVWHVWSZDVFRQVLGHUHGVLJQL¿FDQW 5HVXOWV2XU¿QGLQJVVKRZHGWKDWDPRQJWKHWHVWHGOHFWLQVRQO\*DO1$FUHVLGXHVHQVLtive lectins showed regulated changes in paraxial mesenchyme. Reactions of WFA and MPA lectins with paraxial mesenchyme were severe on GD9. Reactions of WFA continXHG WR *' FRQVWDQWO\ ZKLOH 03$ UHDFWLRQV FRQWLQXHG VWURQJO\ WR *' VLJQL¿FDQWO\ GHFUHDVHGWKHUHDIWHUSDQGWKHQGLVDSSHDUHG99$DQG6%$ELQGLQJVLQLWLDWHG ZHDNO\ RQ *' DQG FRQWLQXHG WR *' ZLWKRXW FKDQJLQJ7KHVH UHDFWLRQV LQFUHDVHG VLJQL¿FDQWO\ S WKHUHDIWHU EHFDPH VHYHUH WR *' DQG ODWHU GLVDSSHDUHG7KH other tested lectins did not reveal regulated changes. &RQFOXVLRQ$FFRUGLQJWRWKHVH¿QGLQJVLWFDQEHFRQFOXGHGWKDWRQO\WKH*DO1$FWHUPLnal sugar showed temporally regulated changes during the early embryonic development of vertebrae in mice. Therefore it most likely plays a key role (s) in the development of vertebrae, especially in the conversion of mesenchymal cells into chondroblasts. The other tested terminal sugars may have no role in this phenomenon. Keywords: Embryonic, Glycoconjugate, Terminal Sugar, Mesenchyme Cell Journal(Yakhteh), Vol 14, No 2, Summer 2012, Pages: 130-141 &LWDWLRQ +DVVDQ]DGHK7DKHUL00(EUDKLP]DGHK%LGHVNDQ$50LUL055HJXODWRU\FKDQJHVRI1DFHW\OJDODFWRVD PLQHWHUPLQDOVXJDULQHDUO\PRXVHHPEU\RQLFSDUD[LDOPHVHQFK\PH&HOO- Introduction 'XULQJHDUO\GHYHORSPHQWRIWKHYHUWHEUDWHHPbryo, the primary segmented tissue of the body axis is the paraxial mesoderm that lies bilaterally to the D[LDORUJDQVQHXUDOWXEHDQGQRWRFKRUG7KH term for the segmented aggregates cell is somites 1H[WWKHVHFHOOVGLIIHUHQWLDWHDQGWKHYHQWUR medial portion changes into its mesenchymal form CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 130 Regulatory Changes of GalNAc in Paraxial Mesenchyme (sclerotome), which are the precursor cells for verWHEUDHULEVDQGLQWHUYHUWHEUDOGLVFV The molecular control of somite differentiation and sclerotome proliferation and differentiation has only VRPHZKDWEHHQHOXFLDWHGLQERWKFKLFNHQDQGPRXVH PRGHOV7KHVRQLFKHGJHKRJVKKVLJQDOLQJPROHFXOHDQGVHYHUDOWUDQVFULSWLRQIDFWRUVLQFOXGing members of the pax and soxIDPLOLHVDUHUHTXLUHG IRUWKHVHSKHQRPHQDWRRFFXU,WLVZHOONQRZQ that the notochord induces sclerotomal cells by secretion of inductive factors such as Shh and Noggin, among others, to migrate, proliferate, differentiate, and adhere to one another for creating vertebrae (7, 7KHGHYHORSPHQWRIWKHYHUWHEUDOFROXPQ in vertebrates is a complex phenomenon that is correlated with distinct morphological and biochemical alterations of the mesenchymal component, such as: induction, cell migration, differentiation, recognition, adhesion, aggregation, condensation, and transformation which is regulated by different subsets of morSKRJHQHV,WFDQEHDVVXPHGWKDWVWUXFWXUDO PRGL¿FDWLRQRIJO\FRFRQMXJDWHVDUHLQYROYHGLQWKHVH SURFHVVHV Glycoconjugates are present at animal cell surfaces DQGLQWKHH[WUDFHOOXODUPDWUL[(&07HUPLQDO sugars of these macromolecules correlate with essential functions of cellular interactions such as cell recognition, receptor function, cell adhesion, and migraWLRQ7KH\FDQEHGHWHFWHGKLVWRFKHPLFDOO\XVLQJ natural polypeptides (lectins), which are obtained IURPSODQWRUDQLPDOVRXUFHV 'HVSLWHH[WHQVLYHVWXGLHVRQWKHXVHRIOHFWLQKLVWRFKHPLVWU\LQWKHGHYHORSPHQWRIFHUWDLQRUJDQV>VPDOO DQGODUJHLQWHVWLQHWHVWLVSURVWDWHSODcenta (20), and differentiation of chondrocytes (21, 22), few studies have focused on the development of WKHYHUWHEUDOFROXPQE\WKLVWHFKQLTXH Studies focusing on the expression of glycoconjugates and their role (s) in vertebral column developPHQWDUHOLPLWHG,QDVWXG\FRQGXFWHGE\*|W]DQG colleagues in 1991, the lectin binding pattern in the embryonal and early fetal human vertebral column ZDVVWXGLHG,QWKH\UHSRUWHGRQWKHOHFWLQ binding pattern in the human paraxial mesenchyme DQGLQWKH\VWXGLHGWKHGLVWULEXWLRQRIJO\coconjugates in the notochord and axial mesenchyme RIKXPDQHPEU\RV%DJQDOODQG6DQGHUV VWXGLHGWKHELQGLQJSDWWHUQRI31$OHFWLQDVVRFLDWHG with sclerotome migration during the formation of CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 131 YHUWHEUDOD[LVLQFKLFNHPEU\RV4XRQGDPDWteo et al. noted that in undulated mouse mutants (substitution in the Pax1 gene), a malformation not only occurred in the vertebral column, but the glycosylation pattern was also altered in normal DQG PDOIRUPHG RUJDQV 0RLLQ HW DO VWXGLHG changes in the terminal sugars of glycoconjugates in precursor cartilage that formed the vertebrae in rat embryos (27). Expression and changes of some terminal carbohydrate residues of glycoconjugates were studied during the conversion of mesenchyme to cartilage forming vertebrae in mouse HPEU\RVYLD:)$DQG2)$OHFWLQVE\1LNUDYHVK HWDOLQ The aim of the present study was to investigate the lectin binding pattern of paraxial mesenchyme forming vertebrae and their possible alterations durLQJHDUO\PRUSKRJHQHVLVLQ%DOEFPRXVHHPEU\RV by means of the lectin histochemistry method. Materials and Methods Preparation of mouse embryos )RU WKLV GHVFULSWLYHDQDO\WLF VWXG\ VH[XDOO\ PDWXUH DGXOW YLUJLQ IHPDOH %DOE& PLFH DYHUDJH DJHZHHNVDJHWKDWZHLJKHGJDQGIHUtile males of the same strain were obtained from the 5D]L,QVWLWXWHLQ0DVKKDG7KH\ZHUHLQGLYLGXDOO\ FDJHGLQDQDQLPDOKRXVHIRUWZRZHHNVEHIRUHH[DPLQDWLRQIRUDGDSWDWLRQDWWKH0DVKKDG8QLYHUVLW\ RI0HGLFDO6FLHQFHV0DVKKDG,UDQ Animals were fed standard laboratory chow and water ad libitum, under controlled conditions (12 KRXUOLJKWGDUNF\FOHÛ&UHODWLYH humidity). $QLPDOV ZHUH PDWHG RYHUQLJKW IHPDOH PDOH LQ VHSDUDWH FDJHV DQG VXEVHTXHQWO\ H[DPined the next morning for the presence of a vaginal SOXJWKDWFRQ¿UPHGSUHJQDQF\WKHVDPHGD\ZDV UHJDUGHG DV JHVWDWLRQDO GD\ *' )URP *' WR*'IRXUSUHJQDQWPLFHZHUHUDQGRPO\VDFUL¿FHGE\FHUYLFDOGLVORFDWLRQIRUHDFKVWDJH(Pbryos were dissected and freed carefully from the uterus and extraembryonic membranes (mean numEHUVRIHPEU\RVZHUHIRUHDFKSUHJQDQWPRXVH All protocols for the animal experiments were apSURYHGE\WKH,QVWLWXWLRQ¶V$QLPDO&DUH&RPPLWWHH RIWKH0DVKKDG8QLYHUVLW\RI0HGLFDO6FLHQFHV Hassanzadeh Taheri et al. ,QWULQVLFSHUR[LGDVHDFWLYLW\ZDVEORFNHGZLWKK\GURJHQSHUR[LGHPHWKDQROIRUPLQXWHV LQ WKH GDUN $OO VHFWLRQV ZHUH LQFXEDWHG with chosen lectins in a humid chamber at room temperature for 2 hours. After extensive rinising in 3%6VHFWLRQVZHUHLQFXEDWHGLQGLDPLQREHQ]LGLQH '$%K\GURJHQ SHUR[LGDVH VXEVWUDWH PHGLXP S+ IRU PLQXWHV DW URRP WHPSHUDWXUH All sections were counterstained with a 1% soluWLRQ RI DOFLDQ EOXH DW S+ IRU PLQXWHV )LQDOO\WKHVHFWLRQVZHUHGHK\GUDWHGFOHDUHG and mounted on glass slides. Controls for lectin staining were carried out as such: substitution of XQFRQMXJDWHGOHFWLQIRUOHFWLQ+53FRQMXJDWHVDQG H[SRVXUHRIVHFWLRQVWR+53DQGVXEVWUDWHPHGLXP without lectin. Preparation of tissue sections :KROHHPEU\RVZHUHZDVKHGLQQRUPDOVDOLQHDQG VXEVHTXHQWO\¿[HGLQ%*¿[DWLYHVRGLXPDFHWDWH PHUFXULF FKORULGH JOXWDUDOGHK\GH overnight at room temperature. After specimen dehydration by passing through a series of successive graded ethanols, the embryos were cleared with xyOHQHDQGHPEHGGHGLQSDUDI¿QEORFNV$URWDU\PLcrotome were used to cut transverse serial sections RIPPWKLFNQHVVHV Lectin histochemistry Seven horseradish peroxidase-conjugated lectins (Table 1) were purchased from Sigma ChemiFDO &RPSDQ\ 86$ DQG GLOXWHG ZLWK SKRVSKDWH EXIIHUHGVDOLQH3%6WRJRIOHFWLQLQ 03%6/HFWLQVFRQVLVWHGRIGlycin max 6%$ 0DFOXUD SRPLIHUD 03$ :LVWDULD ÀRULEXQGD :)$ DQG9LFLD YLOORVD 99$ ZKLFK DOO RI WKHP DUH VSHFL¿F IRU 1DFHW\OJDODFWRVDPLQH (GalNAc), 8OH[ HXURSLXV 8($ ELQGV WR Į/ IXFRVH ZKHDW JHUP DJJOXWLQLQ :*$ ELQGV WR VLDOLFDFLGDQG*ULIIRQLDVLPSOLFLIROLD*6$% binds to galactose terminal sugars). 7KH DI¿QLWLHV RI WKH WHVWHG OHFWLQV ZHUH VHSDrately observed by three examiners blinded to the OHFWLQVXQGHUDOLJKWPLFURVFRSH2O\PSXV$+ and grading was done according to the intensity of lectin reactions with the specimen, from negaWLYH WR VHYHUH 7KH PHGLXP RI the suggested grades for each lectin on each day was calculated. Five sections of the thoracic region of each embryo were chosen randomly. The specimens were deparDI¿QL]HGLQ[\OHQHDQGK\GUDWHGE\SDVVLQJLQDVHries of reduced grades ethanol. They were then treated ZLWK/XJRO¶VVROXWLRQWRUHPRYHPHUFXULFVDOWVSULRU to histochemical staining. Thereafter the sections ZHUHULQVHGIRUPLQXWHVLQ03%6S+ Comparisons were then made among the various tested lectins and also across the different W\SHVRIWLVVXHVDQGVWDJHVRIGHYHORSPHQW'DWD ZHUHDQDO\VHGE\XVLQJ6366VRIWZDUHYHUVLRQ DQG QRQSDUDPHWULF .UXVNDO :DOOLV WHVW GLIIHUHQFHV OHVV WKDQ S ZHUH FRQVLGHUHG VLJQL¿FDQW 7DEOH/LVWRIOHFWLQVWKDWZHUHWHVWHGLQWKHSUHVHQWVWXG\DQGWKHLUPDLQVXJDUVSHFL¿FLWLHV Lectin tested Abbreviation &DUERK\GUDWHELQGLQJVSHFL¿FLW\ Hairy winter vetch (Vicia villosa agglutinin) VVA ȕ*DOĺĮ*DO1DF!*DO Glycine max (Soybean agglutinin) 6%$ Įȕ'*DO1DF!Įȕ'*DO :LVWDULDÀRULEXQGD :)$ Į'*DO1DFȕ'*DO1DF Maclura pomifera agglutinin 03$ *DOȕĺ*DO1DF Ulex europeus agglutinin 8($ Į/)XFĮĺ*DOȕĺ*OF1DFȕ Triticum vulgaris (Wheat germ agglutinin) :*$ >ȕĺ'*OF1DF@RU6LDOLFDFLG Griffonia simplicifolia *6$% '*DO Fuc; Fucose, Gal; Galactose, GalNac; N-Acetylgalactosamine and Glc; Glucose. CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 132 Regulatory Changes of GalNAc in Paraxial Mesenchyme Results Somatic cell differentiation was noted in the craniocaudal direction with time progression, their histomorphological and histochemical changes were evaluated by comparing similar sections in GLIIHUHQW*'V Histomorphology 8VLQJFRQYHQWLRQDOVWDLQLQJ+(WKHFKDUactristic pattern of somatic cell differentiation and development of vertebrae occurred as follows: 2Q *' WKH HSLWKHOLDO FHOOV EHJDQ WR GHWDFK from the ventro-medial portion of the somite and transformed into mesenchymal cells, termed sclerotom (Fig 1). 2. The sclerotomal cells initiated migration to the periphere of the axial structures, notochord, and neural tube, and accumulated around them )LJV 7KHVHPHVHQFK\PDOFHOOVZHUHFRQGHQVHGDQG gradually a prechondroginous blastema formed ZLWKRXWDFOHDUO\GHILQHGPDUJLQ)LJV $IWHUGD\VWKHHPEU\RQLFFDUWLODJHZDV FRPSRVHG RI FORVHO\ SDFNHG FKRQGURF\WHV DQG (&0)LJV Fig 1: Photomicrograph of GD9 mouse embryo, crosssection of paraxial mesenchyme, notochord, and ventral portion of neural groove incubated with VVA lectin. Notochordal process (Small star), Neural groove (Big star), DA; Dorsal aorta, PG; Primitive gut, IEC; Intera embryonic coelum Intra-embryonic coelom (×400). CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 133 Fig 2: Photomicrograph of GD10 mouse embryo, cross-section of paraxial mesenchyme, notochord, and ventral portion of neural tube incubated with WFA lectin. Notochordal plate (n), its sheath (small arrow), neural tube (star), DA; Dorsal aorta. Severe reaction observed in paraxial mesenchyme (arrow; ×200). Fig 3: Photomicrograph of GD10 mouse embryo, crosssection of paraxial mesenchyme, notochord, and ventral portion of neural tube and primitive gut, incubated with SBA lectin. Notochordal plate (n), its sheath (arrow), neural tube (star), DA; Dorsal aorta, PG; Primitive gut (×200) . Hassanzadeh Taheri et al. Fig 4: Photomicrograph of GD10 mouse embryo, crosssection of paraxial mesenchyme, notochord, and ventral portion of neural tube, incubated with MPA lectin. Notochord (big arrow), its sheath (small arrow), neural tube (star), C; Coelum Coelom. Severe reaction observed in mesenchymal surfaces (head arrow) and in ECM (medium arrow) (×200). Fig 6: Photomicrograph of GD11 mouse embryo, crosssection of paraxial mesenchyme, notochord, and ventral portion of neural tube, incubated with MPA lectin. Notochord (n), its sheath (small arrow), neural tube (star), A; Aorta. Severe reaction observed in paraxial mesenchyme (big arrow) (×200). Fig 5: Photomicrograph of GD12 mouse embryo, cross-section of paraxial mesenchyme, notochord, and ventral portion of neural tube incubated with WFA lectin. Notochord (n), reaction of its cells (head of arrow), neural tube (star), A; Aorta. Severe reaction observed in paraxial mesenchyme (arrow) (×200). Fig 7: Photomicrograph of GD13 mouse embryo, crosssection of paraxial mesenchyme, notochord, and ventral portion of neural tube, incubated with VVA lectin. Severe reaction observed in paraxial mesenchyme around the notochord. Notochord (N), Neural tube (star) (×200). CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 134 Regulatory Changes of GalNAc in Paraxial Mesenchyme Lectin histochemistry Reactions of glycoconjugates with tested lectins RQ GLIIHUHQW *'V ZHUH VWXGLHG DQG ¿QGLQJV KDYH EHHQVXPPDUL]HGLQWDEOH WFA Fig 8: Photomicrograph of GD13 mouse embryo, crosssection of paraxial mesenchyme, notochord, and ventral portion of neural tube, incubated with SBA lectin. Notochord (n), neural tube (star). Severe reaction observed in paraxial mesenchyme (white stars) (×200). A severe reaction of paraxial mesenchyme was IRXQGLQDOOVSHFLPHQVLQYHVWLJDWHG)LJV$W KLJKPDJQL¿FDWLRQWKLVVWDLQLQJZDVSUHVHQWRQWKH F\WRSODVPFHOOVXUIDFHDQG(&07KHQRWRFKRUG its sheath, vessel wall, and neuroepithelial cells (especially at the apical plasma membrane of the luminal cells) also showed strong staining. MPA Reactions of this lectin were similar to those of :)$EXWFRQWLQXHGRQO\WR*'DQGWKHUHDIWHU GHFUHDVHG VLJQL¿FDQWO\ DW *' S DQG GLVDSSHDUHG)LJV SBA 7KLV OHFWLQ UHDFWHG ZHDNO\ ZLWK SDUD[LDO PHVHQFK\PH RQ *' DQG FRQWLQXHG ZLWKRXW FKDQJH WR *' DIWHU ZKLFK LW LQFUHDVHG VLJQL¿FDQWO\SDQGZDVDVVHVVHGDVVWURQJ 7KLV UHDFWLRQ GHFUHDVHG VLJQL¿FDQWO\ DJDLQ RQ *' S DQG EHFDPH QHJDWLYH 5HDFtions of the notochord and its sheath were moderate, while neuroepithelial cells, especially at the apical plasma membrane of the luminal cells VKRZHGDVWURQJUHDFWLRQ)LJV VVA Fig 9: Photomicrograph of GD13 mouse embryo, cross-section of paraxial mesenchyme, notochord, and ventral portion of neural tube incubated with GSA1-B4 lectin. Notochord (arrow), neural tube (star), V; Vessel (×200). CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 135 5HDFWLRQVRIWKLVOHFWLQZHUHQHJDWLYHRQ*' )LJ ZLWK D ZHDN UHDFWLRQ RQ *' DQG FRQWLQXHG ZLWKRXW FKDQJH WR *' 2Q *' these reactions changed significantly (p<0.001) and became strong, especially around the notochord, while the notochord reaction was negaWLYHRQWKLVGD\*' (Fig 7). This reaction FRQWLQXHG WR *' DQG FKDQJHG VLJQLILFDQWO\ WKHUHDIWHU RQ *' S DQG WKHQ GLVDSpeared, except in the periphere of the future vertebral body (Fig 10). Reactions of the neural tube, notochord, and its sheath were negative on WKH*'VVWXGLHG Hassanzadeh Taheri et al. Table 2: Severity of reactions of tested lectins with paraxial mesenchyme on different Gestational dayss Tested GDs Lectins 9 10 11 12 VVA - - SBA - - WFA MPA - - - UEA1 - - - - - - - WGA - GSA1-B4 - - - - - - - Staining intensity based on estimated scale from 0 to +++, with: negative reaction; (-), weak; (+), moderate; (++) and severe; (+++). Fig 10: Photomicrograph of GD15 mouse embryo, cross section of paraxial mesenchyme, notochord and ventral portion of neural tube incubated with VVA lectin. Notochord (N), Neural tube (star), Reaction of this lectin restricted to the peripher zone of future vertebral body. Magnification =×200. UEA1 No reaction of this lectin was observed in the paraxial mesenchyme (Fig 11). SDUD[LDOPHVHQFK\PDOFHOOVGXULQJDOO*'VLQYHVtigated (Fig 12). GSA1-B4 WGA $ ZHDN XQLIRUP VWDLQLQJ ZDV REVHYHG LQ WKH %LQGLQJ RI WKLV OHFWLQ ZLWK SDUD[LDO PHVHQFK\PH was negative in the time period investigated (Fig 9). CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 136 Regulatory Changes of GalNAc in Paraxial Mesenchyme Fig 11: Photomicrograph of GD15 mouse embryo, cross-section of paraxial mesenchyme, notochord, and ventral portion of neural tube incubated with UEA1 lectin. Notochord (N), neural tube (star) (×200). Fig 12: Photomicrograph of GD11 mouse embryo, cross-section of paraxial mesenchyme, notochord, and ventral portion of neural tube incubated with WGA lectin. Notochord (arrow), its sheath (head of arrow), neural tube (star), V; Vessel. Severe reaction only in the notochord (×200). CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 137 Hassanzadeh Taheri et al. Discussion Lectins serve as useful histochemical probes for studying the role of surface carbohydrate moieties in glycoconjugates during normal development, including the vertebral column. In this study seven different lectins were used to determine whether differences could be detected DPRQJYDULRXVFHOOVXUIDFHVDQG(&0LQWKHSDraxial mesenchyme during normal development of the vertebral column in mouse embryos beWZHHQ*'DQG*' ,Q D SUHYLRXV VWXG\ ZH IRXQG 31$ SRVLWLYH terminal sugars in paraxial mesenchyme that changed regulatory and discussed LQ WKH present study another subset of lectins were tested. Among the tested lectins, reactions of 03$ DQG:)$ DSSHDUHG VHYHUH RQ *' UHDFWLRQVRI:)$FRQWLQXHGWR*'ZLWKRXWFKDQJLQJZKLOHUHDFWLRQVRI03$FRQWLQXHGWR*' DQG GLVDSSHDUHG ODWHU 3RVLWLYH UHDFWLRQV RI WKH SDUD[LDOPHVHQFK\PHZLWK:)$OHFWLQLQPRXVH DQG03$LQUDWDQGWKHFRQWULEXWLRQRI their recognition of terminal sugars in the development of the vertebral column have been previously reported. 03$DQG:)$OHFWLQVUHFRJQL]H*DO1$FWHUPLQDOVXJDULQVSDWLDOSDWWHUQV*DOȕĺ*DO1$F DQGĮRUȕ'*DO1$FUHVSHFWLYHO\ =VFKlELW] HW DO KDYH VKRZQ WKDW WKH H[SUHVVLRQ RI *DOȕ ĺ*DO1$F PRLHWLHV GXULQJ the development of the vertebrae in chondroF\WHDQGSHULFKRGULXPPHVHQFK\PHLQUDWV ZKLFKDUHVLPLODUWRRXU¿QGLQJV03$ELQGLQJ sites probably detect glycotopes on the laminin JO\FRSURWHLQ 5HDFWLRQV RI 99$ DQG 6%$ OHFWLQV ZKLFK bind GalNAc terminal sugar in spatial patterns, ȕ *DO ĺ *DO1$F DQG Įȕ'*DO1$F UHspectively. EHJDQLQDVLPLODUPDQQHUWKH\ZHUHZHDNRQ *' DQG GLG QRW FKDQJH XQWLO *' 7KHUHafter, these reactions increased significantly S DSSHDUHG VHYHUHO\ XQWLO *' DQG ODWHU GLVDSSHDUHG S 3RVLWLYH PRGHUate reactions of human paraxial mesenchyme ZLWK6%$OHFWLQKDYHEHHQUHSRUWHGSUHYLRXVO\ E\*|W]DQG4XRQGXPDWWHRZKLFKFRQILUPRXU ILQGLQJV99$OHFWLQKDVEHHQGHVFULEHGDV Į*DO1$FVSHFLILFDQGKDVDVWURQJSUHIHUHQFH IRUWKHĮ*DO1$F6HU7KUVWUXFWXUH6XFKVXJDU binding specificity would be extremely useful in detecting the initiation of 0-glycan biosynWKHVLV 8($ OHFWLQ ZDV XQUHDFWLYH RQ WKH SDUD[LDO mesenchyme during the time period described. This finding has indicated that the terminant Į/IXFLVHLWKHUFRPSOHWHO\ODFNLQJRUPDVNHG by other sugars, such as neuraminic acid and WKXV LV LQDFFHVVLEOH WR WKH OHFWLQ ELQGLQJ Į/ fuc is a typical carbohydrate residue of the OOLQNHG JO\FRSURWHLQ ,Q DFFRUGDQFH ZLWK RXU UHVXOWV =VFKlELW] HW DO GLG QRW ILQG HYLdence for the presence of µĮ/IXF residues in WKHSDUD[LDOPHVHQFK\PH,QFRQWUDVWZLWK our results, the expression of these moieties ZDV UHSRUWHG E\ *|W] DQG 4XRQGXPDWWHR in human embryos. $QRWKHUWHVWHGOHFWLQZDV:*$7KHUHDFWLRQ RIWKLVOHFWLQZDVJHQHUDODQGLQLWLDWHGRQZHDNO\RQ*'DQGWKHQFRQWLQXHGWR*'6LQFH this lectin binds GlcNAc and sialic acid terminal sugars, few glycocojugates with GlcNAc or sialic acid are present in this region. The findLQJVRI=VFKlELW]HWDOIRUWKLVVXJDUZDVQHJDWLYH ZKLOH *|W] HW DO KDYH QRWHG ZHDN staining in the axial mesenchyme (27), which was similar to our findings. This latest invesWLJDWLRQ FRQFOXGHG WKDW DEVHQW RU ZHDN :*$ lectin binding in the axial mesenchyme could be related to migration, because axial mesenchymal cells no longer migrate during the early GHYHORSPHQWRIWKHYHUWHEUDOFROXPQ6Xmida et al. reported that proteins binding Con A DQG:*$OHFWLQVSURPRWHPLJUDWLRQRIFDUGLDF PHVHQFK\PDOFHOOVLQWKHFKLFNHQ *6$% OHFWLQ GLG QRW UHDFW ZLWK WKH SDraxial mesenchyme, therefore no galactose terminal sugar was obtained in this region. In FRQWUDVWWRRXUUHVXOWV=VFKlELW]HWDOUHSRUWHG positive findings of paraxial mesenchyme in UDWV 'XULQJ WKH *'V LQYHVWLJDWHG ILUVW DQ XQVHJmented paraxial mesenchyme was derived from CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 138 Regulatory Changes of GalNAc in Paraxial Mesenchyme sclrotomal cells, then segmentation occurred rapidly for the formation of vertebral bodies, DUFKHVDQGLQWHUYHUWHEUDOGLVFV $FFRUGLQJWR*|W]HWDOWKHD[LDOPHVHQFK\PH of the early human embryo is rich in sulphated glycosaminoglycans and hyaloronic acid and FRQWDLQV JO\FRSURWHLQV OLNH ILEURQHFWLQ DQG ODPLQLQEXWKDVQRNHUDWDQVXOSKDWH7RROH has reported that during cell aggregation in the paraxial mesenchyme, fibronectin, tenascin, DQGW\SH,FROODJHQDFFXPXODWHLQWKH(&0E\ DORVVRIK\DOXURQDWH7KHSUHVHQFHDQGLQvolvement of aggrecans in the process of sclerotomal condensation around the notochord to form the vertebral body has been reported by 9DVDQ 7KH WUDQVLWLRQ WR GHYHORSLQJ FDUWLODJH LV PDUNHG E\ WKH GHSRVLWLRQ RI FDUWLODJH matrix protein, such as proteoglycan core protein, fibronectin, chonroitin sulphate biglycan, and transients from type I and type II collagen )LEURQHFWLQDQGWHQDVFLQFROODERUDWHLQILbroblasts in culture, and this may be an important feature for regulation of cell adhesion, cell PLJUDWLRQDQGPRUSKRJHQHVLV Although there are similarities between our ILQGLQJV DQG SUHYLRXV VWXGLHV differences also exist, which are due to the different species examined. Species differences DUH D ZHOO NQRZQ SKHQRPHQRQ LQ OHFWLQ KLVWRchemistry, and this can explain why our results DUH GLIIHU IURPWKRVHRI *|W]DQG4XRQGXPDWWHRRQKXPDQHPEU\RVDQG=VFKlELW]HWDO RQUDWHPEU\RV Further studies are needed to understand how these specific glycoconjugates and their GalNAc terminal sugers cause morphological changes during early development of the vertebrae. As the contribution of Shh glycoprotein has been estabilished in the development of vertebrae, furWKHU VWXG\ RI LPPXQRKLVWRFKHPLFDOV E\ VSHFL¿F antibodies and lectin histochemistry by tested lectins are recommended. Acknowlegments This research was supported by grant number IURP WKH RIILFH RI WKH 9LFHFKDQFHOORU IRU 5HVHDUFK $IIDLUV DW 0DVKKDG 8QLYHUVLW\ RI 0HGLFDO 6FLHQFHV 7KH DXWKRUV DUH YHU\ JUDWHIXO WR 3URIHVVRUV )D]HO 1LNUDYHVK DQG-DODOLIRUWKHLUJXLGDQFHDQGZRXOGOLNHWR WKDQN0UV0RWDMDGGHGIRUKHUH[FHOOHQWWHFKQLFDODVVLVWDQFH:HDOVRGHFODUHWKDWWKHUHLVQR conflict of interest for this article. References Conclusion 1. According to our results, we have concluded that specific glycoconjugate molecules with GalNAc terminal sugar bind to all specific sensitive tested lectins and show temporally regulated changes, probably in the presence of components of prechondrogenic cells forming the YHUWHEUDH RU LQ WKH (&0 7KHVH FDUERK\GUDWH residues may be involved in phenomena such as transforming somatic epithelial cells to paraxial mesenchyme, migration and aggregation of these cells around axial organs, condensation and proliferation of these cells, and especially contributing to the conversion of mesenchymal CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 cells to chondroblasts. Those GalNAc residues ZKLFKELQG:)$6%$DQG99$OHFWLQVLQDGdition to the mentioned processes), may be correlated with the differentiation of chondrocytes during the development of the vertebrae. Other terminal sugars such as sialic acid, GlcNAc, galactose, and fucosylated moieties, which did not show temporally regulated changes, are probably not involved in the differentiation of the paraxial mesenchyme during early morphogenesis in vertebral column development. 139 2. 5. 3RXUTXLp 2 9HUWHEUDH VRPLWRJHQHVLV D QRYHO SDUDGLJP IRU DQLPDO VHJPHQWDWLRQ" ,QW - 'HY %LRO Williams Pl, Warwick R, Dyson M, Ellis H, Standring 60 +HDO\ -& HW DO *UD\¶V $QDWRP\ 7KH DQDWRPRFDO EDVLV RI PHGLFLQH DQG VXUJHU\ th HG /RQGRQ &KXUFKLOO/LYLQJVWRQH 6DGOHU 7: /DQJPDQ¶V PHGLFDO (PEU\RORJ\ th ed. 3KLODGHOSKLD /LSSLQFRWW :LOOLDPV :LONLQV Lassar AB, Munsterberg AE. The role of positive and negative signals in somite patterning. Curr Opin NeuURELRO :DQJ - /L 6 &KHQ < 'LQJ ; :QWȕFDWHQLQ VLJQDOing controls Mespo expression to regulate segmentaWLRQ GXULQJ [HQRSXV VRPLWRJHQHVLV 'HY %LRO Dockter JL. Sclerotome induction and differentiation. Hassanzadeh Taheri et al. 7. 8. 9. 11. 12. 15. 17. 18. 19. 21. 22. &XUU7RS'HY%LRO Fan CM, Tessier-Lavigne M. Patterning of mammalian VRPLWHVE\VXUIDFHHFWRGHUPDQGQRWRFKRUGHYLGHQFH for sclerotome induction by a hedgehog homolog. Cell. Fleming A, Keynes R, Tannahill D. A central role for the QRWRFKRUGLQYHUWHEUDOSDWWHUQLQJ'HYHORSPHQW 6PLWV3/HIHEYUH96R[DQG6R[DUHUHTXLUHGIRU notochord extracellular matrix sheath formation, notochord cell survival and development of the nucleus SXOSRVXV RI LQWHUYHUWHEUDO GLVFV 'HYHORSPHQW Akiyama H, Chaboissier MC, Martin JF, Schedl A, de Combrugghe B. The transcription factor Sox 9 has essential roles in successive steps of the chondrocyte differentiation pathway and is required for expression of VR[DQGVR[*HQ'HY Fleming A, Keynes RJ, Tannahill D. The role of the noWRFKRUG LQ YHUWHEUDO FROXPQ IRUPDWLRQ - $QDW 3W Zhang G. An evo-devo view on the origin of the backERQH HYROXWLRQDU\ GHYHORSPHQW RI WKH YHUWHEUDH ,QWHJU&RPS%LRO Götz W, Quondumatteo F. Glycoconjugate distribution in early human notochord and axial mesenchyme. Acta +LVWRFKHP Debray H, Decont D, Strecker G, Spik G, Montrcuil J. Specificity of twelve lectins towards oligosaccharides and glycopeptides related to N-glycosylproteins. Eur J %LRFKHP Edelman GM. Cell adhesion molecule expression and the regulation of morphogenesis. Cold Spring Harb 6\PS4XDQW%LRO Adam E, Dziegielewska KM, Saunders NR, Schumacher U. Neuraminic acid specific lectins as markers of early cortical plate neurons. Int J Dev Neurosci. Zanuzzi CN, Barbeito CG, Ortíz ML, Lozza FA, Fontana PA, Portiansky EL, et al. Glycoconjugate histochemistry in the small and large intestine of normal and Solanum glaucophyllum-intoxicated rabbits. Res 9HW6FL Valbuena G, Madrid JF, Hernández F, Sáez FJ. Identification of fucosylated glycoconjugates in Xenopus laevis testis by lectin histochemistry. Histochem Cell %LRO Miyanaka H, Nakamura T, Nishi N. Tissue-specific expression of fucosylated glycosphingolipid species LQ UDW SURVWDWH %LRVFL %LRWHFKQRO %LRFKHP Jeschke U, Toth B, Scholz C, Friese K, Makrigiannakis A. Glycoprotein and carbohydrate binding protein expression in the placenta in early pregnancy loss. J 5HSURG,PPXQRO Toegel S, Harrer N, Plattner VE, Unger FM, Viernstein H, Goldring MB, et al. Lectin binding studies on C-28/ I2 and T/C-28a2 chondrocytes provide a basis for new tissue engineering and drug delivery perspectives in FDUWLODJH UHVHDUFK - &RQWURO 5HOHDVH 121-129. Toegel S, Pabst M, Wu SQ, Grass J, Goldring MB, Chiari C, et al. Phenotype-related differential alpha-2, RU DOSKDVLDO\ODWLRQ RI JO\FRSURWHLQ 1JO\FDQV LQ KXPDQ FKRQGURF\WHV 2VWHRDUWKULWLV &DUWLODJH Götz W, Fischer G, Herken R. Lectin binding pattern in the embryonal and early fetal human vertebral column. Anat (PEU\RO%HUO Götz W, Frisch D, Osmers R, Herken R. Lectin-binding patterns in the embryonic human paraxial mesenchyme. $QDW(PEU\RO%HUO 25. Bagnall KM, Sanders EJ. The binding pattern of peanut lectin associated with sclerotome migration and the formation of the vertebral axis in the chick embryo. Anat EmEU\RO%HUO Quondamatteo F, Zieger J, Götz W, Miosge N, Herken R. Extensive glycosylation changes revealed by lectin histochemistry in morphologically normal prenatal tissues RIWKHPRXVHPXWDQWXQGXODWHGXQXQ$QDW5HF ± 27. Moiin AA, Heidari Z, Fazel AR. Histochemical study of developing cartilage of primordial vertebrae in rat embryo. &HOO-RXUQDO<DNKWHK 28. Nikravesh MR, Fazel A, Jalali M. From mesenchyme to FDUWLODJH/HFWLQKLVWRFKHPLFDOVWXGLHVRIYHQWURPHGLal mesenchyme to the developing neural tube during HPEU\RQLF SHULRG ,UDQ - %DVLF 0HG 6FL 29. Ahi M, Zamansoltani F, Hassanzadeh Taheri MM, Ebrahimzadeh Bideskan AR. The role of GalNac terminal sugar on adrenal gland development. Adv Biol Res. Hassanzadeh Taheri MM, Nikravesh MR, Djalali M, Fazel $5(EUDKLP]DGHK$5'LVWULEXWLRQRIVSHFL¿FJO\FRFRQjugates in early mouse embryonic notochord and paraxial PHVHQFK\PH,%- Ebrahimzadeh Bideskan AR, Hassanzadeh Taheri MM, Nikravesh MR. Lectin histochemical study of vasculogenesis during rat pituitary morphogenesis. Iran J Bas Med 6FL Zschäbitz A, Krahn V, Gabius HJ, Weiser H, Khaw A, Biesalski HK, et al. Glycoconjugate expression of chondrocytes and perichondrium during hyaline cartiODJH GHYHORSPHQW LQ WKH UDW -$QDW 3W Buse E, Seifert H. Glycoconjugate expression during HDUO\PRXVHRFXORJHQHVLV+LVWRFKHP- 819-827. Piller V, Piller F, Cartron JP. Comparison of the carbohydrate-binding specificities of seven N-acetyl-D-gaODFWRVDPLQHUHFRJQL]LQJOHFWLQV(XU-%LRFKHP 3DULOOR)$ULDV036XSSOL]L$9*O\FRSUR¿OHRIWKHGLIIHUent cell types present in the mucosa of the horse guttural SRXFKHV7LVVXH&HOO Sumida H, Nakamura H, Thompson RP, Yasuda M. Binding of lectins to novel migration promoters on cardiac mesenchymal cells in the chick. Cell Struc Funct. Christ B, Wilting J. From somites to vertebral column. Ann $QDW Götz W, Osmers R, Herken R. Localisation of extracellular matrix components in the embryonic human noWRFKRUGDQGD[LDOPHVHQFK\PH-$QDW3W Toole B, Trelstad RL. Hyaluronate production and removal during corneal development in the chick. Dev %LRO Vasan N. Analysis of perinotochordal materials. I. StudLHV RQ SURWHRJO\FDQV V\QWKHVLV - ([S =RRO CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 140 Regulatory Changes of GalNAc in Paraxial Mesenchyme Mina M, Kollar EJ, Upholte WB. Temporal and spatial expression of genes for cartilage extracellular matrix proteins during avian mandibular arch development. 'LIIHUHQWLDWLRQ CELL JOURNAL(Yakhteh), Vol 14, No 2, Summer 2012 141 Tremble P, Chiquet-Ehrismann R, Werb Z. The extracellular matrix ligands fibronectin and tenascin collaborate in regulating collagenase gene expression in ILEUREODVWV0RO%LRO&HOO