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Does tenascin affect integrin function?
Cell Biology International
s49
Reports, Vol. 14, Abstracts Supplement
THE CDll/CD18 AND ICAM HUMAN LEUKOCYTE ADHESION MOLECULES
Carl G. Gahmberg, Manuel Patarroyo, Carmela Kantor, Pekka Nortamo, Pekka Kotovuori. Department of Eiochemistry, University of Helsinki, Helsinki, Finland. Leukocyte adhesion is of fundamental importance for a number of leukocyte functions like cytotoxiantibody production, chemotaxis, phagocytosis city, etc. We and others have shown that the CDlla/CD18, CDllb/CD18 and CDllc/CD18 receptor molecules play a central role in these phenomena. The receptors consist of a unique a-chain (CDll) and a common Bchain (CD18). These have all been sequenced, and the analysis shows that the proteins belong to the integrin superfamily of adhesion receptors. Allthese polypeptides are type I transmembrane proteins with relatively short intracellular regions. The CLchains contain binding sites for Ca++, and divalent cations are needed for adhesive functions. The 6chain contains a cysteinrich region near the membrane, which may be important for activity. The polypeptides are N-glycosylated, and the structures of the oligosaccharides have recently been determined. The CDlla/CD18 integrin which is enriched on lymphocytes, binds to the ICAMand ICAMmolecules. These evidently have a wide cellular distribution. The ICAMmolecule is induced in many cells by various substances. The ICAMmolecule was cloned using an adhesion assay (Springer et al.), but the protein has not previously been identified. We have synthesized the ICAMDNA, expressed in mammalian cells and bacteria, made an antiserum, and identified it on leukocytes and endothelial cells. This will be discussed in detail.
FUNCTIONALANALYSISANDTOPOGRAPHYOF INTJXGRINSINHUMANEPITHELIALCELLS P.C.Marchisio',M.DeLuca*,S.Bondanza*,O.Cremona“,H.M.Co~,R. Cancedda*andV.Qu~,ODip.diScienzeBiamedicheeOncologiaUniv.di Torino,10126Torino,Italy,*IST,Ist.Naz.perlaRicercasulCancro,16132 Genova.Italy,ADept.ofImmunology,ResearchInstituteofScrippsClinic,La Jolla.CA92037. ?hedistributionofintegrinsincoloniesofhumankeratinocytesin vitroas well aslndlfferemlinesofepilhelialtumorcellswasstudiedusinglmmunoflu~~.Inagnemanwithbiaheml*11studies,antibodiestotheSlanda0 chains,butnottotheEZuld83chains,werefnudtoreactwitb epithelialcek. Antibodiestotheavchainlmmuno0reciuitatedanew l3chaln(llS).Distlnct
s51
1990
17
DOES TEHASCIN AFFECT INTEZRIN FUNCTION? Ruth Chiquet-Ehrismann, Urs Hofer and Friedrich Miescher Institut, Jiirg Spring, P.O.Box 2543, CH-4002 Basel, Switzerland. Tenascin (Tn) and fibronectin (Fn) are two major extracellular matrix glycoThe tissue distribution of Tn is proteins. much more restricted in comparison to Fn. For human Fn it has been shown that the is one of the cellular a5131 integrin Since we have found that Tn receptors. inhibits Fn-mediated cell adhesion we wanted to test whether Tn affects the We thus isofunction of a 0, integrin. lated the chic 2 en a5B1 integrin and raised subunit-specific monoclonal antibodies. as-specific antibody The revealed a codistribution of this receptor with Fn in cultured chick embryo fibroblasts, but in sections of chick embryos the codistribution with Fn was limited. In 14d embryonic lung Fn staining was ubiquitous, whereas the as-antibody only stained the presumptive cartilage rings around the bronchi colocalizing with Tn. Thus a513, integrin does not seem to be the major Fn receptor in vivo, but may be important at restricted locations only. Using the a5antibody for affinity chromatography we isolated from cell exract besides a5Rl integrin an additional protein band to which on gel blots Tn as well as Fn were binding. Thus it is possible that a associated proteins are involved in t 3 e transmission of the contrary effects of Tn and Fn on cell shape.
s50
GENETIC CONTROL OF CELL DEATH IN THE NEMATODE C. ELEGANS H. Robert Horvitz, Howard Hughef Medical Institute, Depr. Biology, MIT, Cambridge, MA 02139 USA Wb have been analyzing the genetic control of cell death in the nomntode Caonorhnbdicis dG!~ilnf. Of the 1090 nuclei generated during
S52
noxmal development of the C. elegans 131 die. Ue have idcntifiod and chnractorized 11 geneo that function in all 131 of these programmed cell deaths. Three of these gene8 control the onset of the death process,
hermaphrodite,
seven act in the engulfment of dying cells by in the their neighbors, and one functions digestion of the DNA of cell corpate. Three additional genes specify which cells will or will not express this cell death program. We have also identified two genes that can mutate to ceuso cella to die by A process chat is diotinct from that controlling the programmed cell deaths.
s49
Reports, Vol. 14, Abstracts Supplement
THE CDll/CD18 AND ICAM HUMAN LEUKOCYTE ADHESION MOLECULES
Carl G. Gahmberg, Manuel Patarroyo, Carmela Kantor, Pekka Nortamo, Pekka Kotovuori. Department of Eiochemistry, University of Helsinki, Helsinki, Finland. Leukocyte adhesion is of fundamental importance for a number of leukocyte functions like cytotoxiantibody production, chemotaxis, phagocytosis city, etc. We and others have shown that the CDlla/CD18, CDllb/CD18 and CDllc/CD18 receptor molecules play a central role in these phenomena. The receptors consist of a unique a-chain (CDll) and a common Bchain (CD18). These have all been sequenced, and the analysis shows that the proteins belong to the integrin superfamily of adhesion receptors. Allthese polypeptides are type I transmembrane proteins with relatively short intracellular regions. The CLchains contain binding sites for Ca++, and divalent cations are needed for adhesive functions. The 6chain contains a cysteinrich region near the membrane, which may be important for activity. The polypeptides are N-glycosylated, and the structures of the oligosaccharides have recently been determined. The CDlla/CD18 integrin which is enriched on lymphocytes, binds to the ICAMand ICAMmolecules. These evidently have a wide cellular distribution. The ICAMmolecule is induced in many cells by various substances. The ICAMmolecule was cloned using an adhesion assay (Springer et al.), but the protein has not previously been identified. We have synthesized the ICAMDNA, expressed in mammalian cells and bacteria, made an antiserum, and identified it on leukocytes and endothelial cells. This will be discussed in detail.
FUNCTIONALANALYSISANDTOPOGRAPHYOF INTJXGRINSINHUMANEPITHELIALCELLS P.C.Marchisio',M.DeLuca*,S.Bondanza*,O.Cremona“,H.M.Co~,R. Cancedda*andV.Qu~,ODip.diScienzeBiamedicheeOncologiaUniv.di Torino,10126Torino,Italy,*IST,Ist.Naz.perlaRicercasulCancro,16132 Genova.Italy,ADept.ofImmunology,ResearchInstituteofScrippsClinic,La Jolla.CA92037. ?hedistributionofintegrinsincoloniesofhumankeratinocytesin vitroas well aslndlfferemlinesofepilhelialtumorcellswasstudiedusinglmmunoflu~~.Inagnemanwithbiaheml*11studies,antibodiestotheSlanda0 chains,butnottotheEZuld83chains,werefnudtoreactwitb epithelialcek. Antibodiestotheavchainlmmuno0reciuitatedanew l3chaln(llS).Distlnct
s51
1990
17
DOES TEHASCIN AFFECT INTEZRIN FUNCTION? Ruth Chiquet-Ehrismann, Urs Hofer and Friedrich Miescher Institut, Jiirg Spring, P.O.Box 2543, CH-4002 Basel, Switzerland. Tenascin (Tn) and fibronectin (Fn) are two major extracellular matrix glycoThe tissue distribution of Tn is proteins. much more restricted in comparison to Fn. For human Fn it has been shown that the is one of the cellular a5131 integrin Since we have found that Tn receptors. inhibits Fn-mediated cell adhesion we wanted to test whether Tn affects the We thus isofunction of a 0, integrin. lated the chic 2 en a5B1 integrin and raised subunit-specific monoclonal antibodies. as-specific antibody The revealed a codistribution of this receptor with Fn in cultured chick embryo fibroblasts, but in sections of chick embryos the codistribution with Fn was limited. In 14d embryonic lung Fn staining was ubiquitous, whereas the as-antibody only stained the presumptive cartilage rings around the bronchi colocalizing with Tn. Thus a513, integrin does not seem to be the major Fn receptor in vivo, but may be important at restricted locations only. Using the a5antibody for affinity chromatography we isolated from cell exract besides a5Rl integrin an additional protein band to which on gel blots Tn as well as Fn were binding. Thus it is possible that a associated proteins are involved in t 3 e transmission of the contrary effects of Tn and Fn on cell shape.
s50
GENETIC CONTROL OF CELL DEATH IN THE NEMATODE C. ELEGANS H. Robert Horvitz, Howard Hughef Medical Institute, Depr. Biology, MIT, Cambridge, MA 02139 USA Wb have been analyzing the genetic control of cell death in the nomntode Caonorhnbdicis dG!~ilnf. Of the 1090 nuclei generated during
S52
noxmal development of the C. elegans 131 die. Ue have idcntifiod and chnractorized 11 geneo that function in all 131 of these programmed cell deaths. Three of these gene8 control the onset of the death process,
hermaphrodite,
seven act in the engulfment of dying cells by in the their neighbors, and one functions digestion of the DNA of cell corpate. Three additional genes specify which cells will or will not express this cell death program. We have also identified two genes that can mutate to ceuso cella to die by A process chat is diotinct from that controlling the programmed cell deaths.