{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T03:32:27Z","timestamp":1782790347305,"version":"3.54.5"},"reference-count":32,"publisher":"American Society of Hematology","issue":"18","content-domain":{"domain":["ashpublications.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2018,9,25]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Activation of platelet glycoprotein IIb-IIIa (GPIIb-IIIa; integrin \u03b1IIb\u03b23) leads to high-affinity fibrinogen binding and platelet aggregation during hemostasis. Whereas GTP-bound Rap1 GTPase promotes talin 1 binding to the \u03b23 cytoplasmic domain to activate platelet GPIIb-IIIa, the Rap1 effector that regulates talin association with \u03b23 in platelets is unknown. Rap1 binding to the talin 1 F0 subdomain was proposed to forge the talin 1\u2013Rap1 link in platelets. Here, we report a talin 1 point mutant (R35E) that significantly reduces Rap1 affinity without a significant effect on its structure or expression. Talin 1 head domain (THD) (R35E) was of similar potency to wild-type THD in activating \u03b1IIb\u03b23 in Chinese hamster ovary cells. Coexpression with activated Rap1b increased activation, and coexpression with Rap1GAP1 reduced activation caused by transfection of wild-type THD or THD(R35E). Furthermore, platelets from Tln1R35E\/R35E mice showed similar GPIIb-IIIa activation to those from wild-type littermates in response to multiple agonists. Tln1R35E\/R35E platelets exhibited slightly reduced platelet aggregation in response to low doses of agonists; however, there was not a significant hemostatic defect, as judged by tail bleeding times. Thus, the Rap1\u2013talin 1 F0 interaction has little effect on platelet GPIIb-IIIa activation and hemostasis and cannot account for the dramatic effects of loss of Rap1 activity on these platelet functions.<\/jats:p>","DOI":"10.1182\/bloodadvances.2018020487","type":"journal-article","created":{"date-parts":[[2018,9,21]],"date-time":"2018-09-21T15:59:13Z","timestamp":1537545553000},"page":"2358-2368","update-policy":"https:\/\/doi.org\/10.1182\/blood.2019cm0000","source":"Crossref","is-referenced-by-count":31,"title":["Rap1 binding to the talin 1 F0 domain makes a minimal contribution to murine platelet GPIIb-IIIa activation"],"prefix":"10.1182","volume":"2","author":[{"given":"Frederic","family":"Lagarrigue","sequence":"first","affiliation":[{"name":"Department of Medicine, University of California, San Diego, La Jolla, CA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5373-0176","authenticated-orcid":false,"given":"Alexandre R.","family":"Gingras","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of California, San Diego, La Jolla, CA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David S.","family":"Paul","sequence":"additional","affiliation":[{"name":"McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew J.","family":"Valadez","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of California, San Diego, La Jolla, CA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monica N.","family":"Cuevas","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of California, San Diego, La Jolla, CA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hao","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of California, San Diego, La Jolla, CA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miguel A.","family":"Lopez-Ramirez","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of California, San Diego, La Jolla, CA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3438-2807","authenticated-orcid":false,"given":"Benjamin T.","family":"Goult","sequence":"additional","affiliation":[{"name":"School of Biosciences, University of Kent, Kent, United Kingdom; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sanford J.","family":"Shattil","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of California, San Diego, La Jolla, CA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wolfgang","family":"Bergmeier","sequence":"additional","affiliation":[{"name":"McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC;"},{"name":"Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark H.","family":"Ginsberg","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of California, San Diego, La Jolla, CA;"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"234","published-online":{"date-parts":[[2018,9,21]]},"reference":[{"issue":"6","key":"2020021108365580800_B1","doi-asserted-by":"crossref","first-page":"673","DOI":"10.1016\/S0092-8674(02)00971-6","article-title":"Integrins: bidirectional, allosteric signaling machines","volume":"110","author":"Hynes","year":"2002","journal-title":"Cell"},{"issue":"6","key":"2020021108365580800_B2","doi-asserted-by":"crossref","first-page":"1606","DOI":"10.1182\/blood-2004-04-1257","article-title":"Integrins: dynamic scaffolds for adhesion and signaling in platelets","volume":"104","author":"Shattil","year":"2004","journal-title":"Blood"},{"issue":"4","key":"2020021108365580800_B3","doi-asserted-by":"crossref","first-page":"288","DOI":"10.1038\/nrm2871","article-title":"The final steps of integrin activation: the end game","volume":"11","author":"Shattil","year":"2010","journal-title":"Nat Rev Mol Cell Biol"},{"issue":"3","key":"2020021108365580800_B4","doi-asserted-by":"crossref","first-page":"680","DOI":"10.1172\/JCI22973","article-title":"Rap1b is required for normal platelet function and hemostasis in mice","volume":"115","author":"Chrzanowska-Wodnicka","year":"2005","journal-title":"J Clin Invest"},{"issue":"9","key":"2020021108365580800_B5","doi-asserted-by":"crossref","first-page":"982","DOI":"10.1038\/nm1098","article-title":"CalDAG-GEFI integrates signaling for platelet aggregation and thrombus formation [published correction appears in Nat Med. 2004;10(10):1139.]","volume":"10","author":"Crittenden","year":"2004","journal-title":"Nat Med"},{"key":"2020021108365580800_B6","article-title":"Functional redundancy between RAP1 isoforms in murine platelet production and function primates [published online ahead of print 21 August 2018]","author":"Stefanini","journal-title":"Blood"},{"issue":"18","key":"2020021108365580800_B7","doi-asserted-by":"crossref","first-page":"1796","DOI":"10.1016\/j.cub.2006.08.035","article-title":"Reconstructing and deconstructing agonist-induced activation of integrin alphaIIbbeta3","volume":"16","author":"Han","year":"2006","journal-title":"Curr Biol"},{"issue":"4","key":"2020021108365580800_B8","doi-asserted-by":"crossref","first-page":"585","DOI":"10.1016\/j.devcel.2004.07.021","article-title":"RIAM, an Ena\/VASP and profilin ligand, interacts with Rap1-GTP and mediates Rap1-induced adhesion","volume":"7","author":"Lafuente","year":"2004","journal-title":"Dev Cell"},{"issue":"8","key":"2020021108365580800_B9","doi-asserted-by":"crossref","first-page":"5119","DOI":"10.1074\/jbc.M807117200","article-title":"RIAM activates integrins by linking talin to ras GTPase membrane-targeting sequences","volume":"284","author":"Lee","year":"2009","journal-title":"J Biol Chem"},{"issue":"25","key":"2020021108365580800_B10","doi-asserted-by":"crossref","first-page":"2704","DOI":"10.1182\/blood-2015-05-647453","article-title":"Loss of the Rap-1 effector RIAM results in leukocyte adhesion deficiency due to impaired beta2 integrin function in mice","volume":"126","author":"Klapproth","year":"2015","journal-title":"Blood"},{"issue":"2","key":"2020021108365580800_B11","doi-asserted-by":"crossref","first-page":"219","DOI":"10.1182\/blood-2014-08-597542","article-title":"Rap1-GTP-interacting adaptor molecule (RIAM) is dispensable for platelet integrin activation and function in mice","volume":"125","author":"Stritt","year":"2015","journal-title":"Blood"},{"issue":"25","key":"2020021108365580800_B12","doi-asserted-by":"crossref","first-page":"2695","DOI":"10.1182\/blood-2015-05-644104","article-title":"Rap1 and its effector RIAM are required for lymphocyte trafficking","volume":"126","author":"Su","year":"2015","journal-title":"Blood"},{"issue":"6","key":"2020021108365580800_B13","doi-asserted-by":"crossref","first-page":"1069","DOI":"10.1038\/emboj.2010.4","article-title":"Structure of a double ubiquitin-like domain in the talin head: a role in integrin activation","volume":"29","author":"Goult","year":"2010","journal-title":"EMBO J"},{"key":"2020021108365580800_B14","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s12860-015-0078-0","article-title":"Direct interaction between talinB and Rap1 is necessary for adhesion of Dictyostelium cells","volume":"17","author":"Plak","year":"2016","journal-title":"BMC Cell Biol"},{"issue":"1","key":"2020021108365580800_B15","doi-asserted-by":"crossref","first-page":"1744","DOI":"10.1038\/s41467-017-01822-8","article-title":"Structure of Rap1b bound to talin reveals a pathway for triggering integrin activation","volume":"8","author":"Zhu","year":"2017","journal-title":"Nat Commun"},{"issue":"12","key":"2020021108365580800_B16","doi-asserted-by":"crossref","first-page":"2152","DOI":"10.1016\/j.str.2016.10.001","article-title":"Structural basis of dimeric Rasip1 RA domain recognition of the Ras subfamily of GTP-binding proteins","volume":"24","author":"Gingras","year":"2016","journal-title":"Structure"},{"issue":"4","key":"2020021108365580800_B17","doi-asserted-by":"crossref","first-page":"687","DOI":"10.1002\/prot.20449","article-title":"The CCPN data model for NMR spectroscopy: development of a software pipeline","volume":"59","author":"Vranken","year":"2005","journal-title":"Proteins"},{"issue":"2","key":"2020021108365580800_B18","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1182\/blood.V78.2.369.369","article-title":"Platelet glycoprotein IIb-IIIa (alpha IIb beta 3 integrin) confers fibrinogen- and activation-dependent aggregation on heterologous cells","volume":"78","author":"Frojmovic","year":"1991","journal-title":"Blood"},{"issue":"20","key":"2020021108365580800_B19","doi-asserted-by":"crossref","first-page":"11107","DOI":"10.1016\/S0021-9258(17)39154-8","article-title":"Changes in the platelet membrane glycoprotein IIb.IIIa complex during platelet activation","volume":"260","author":"Shattil","year":"1985","journal-title":"J Biol Chem"},{"issue":"6","key":"2020021108365580800_B20","doi-asserted-by":"crossref","first-page":"1047","DOI":"10.1083\/jcb.124.6.1047","article-title":"Integrin cytoplasmic domains mediate inside-out signal transduction","volume":"124","author":"O\u2019Toole","year":"1994","journal-title":"J Cell Biol"},{"issue":"21","key":"2020021108365580800_B21","doi-asserted-by":"crossref","first-page":"3597","DOI":"10.1242\/dev.035857","article-title":"Talin 1 and 2 are required for myoblast fusion, sarcomere assembly and the maintenance of myotendinous junctions","volume":"136","author":"Conti","year":"2009","journal-title":"Development"},{"issue":"7","key":"2020021108365580800_B22","doi-asserted-by":"crossref","first-page":"1145","DOI":"10.1038\/emboj.2008.30","article-title":"The Rap-RapGAP complex: GTP hydrolysis without catalytic glutamine and arginine residues","volume":"27","author":"Scrima","year":"2008","journal-title":"EMBO J"},{"issue":"12","key":"2020021108365580800_B23","doi-asserted-by":"crossref","first-page":"3435","DOI":"10.1074\/mcp.M114.038513","article-title":"Copy number analysis of the murine platelet proteome spanning the complete abundance range","volume":"13","author":"Zeiler","year":"2014","journal-title":"Mol Cell Proteomics"},{"issue":"2","key":"2020021108365580800_B24","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1002\/cyto.10114","article-title":"Flow cytometric detection of activated mouse integrin alphaIIbbeta3 with a novel monoclonal antibody","volume":"48","author":"Bergmeier","year":"2002","journal-title":"Cytometry"},{"issue":"5","key":"2020021108365580800_B25","doi-asserted-by":"crossref","first-page":"880","DOI":"10.1006\/bbrc.2001.5497","article-title":"Analysis of the mammalian talin 2 gene TLN2","volume":"286","author":"Monkley","year":"2001","journal-title":"Biochem Biophys Res Commun"},{"issue":"13","key":"2020021108365580800_B26","doi-asserted-by":"crossref","first-page":"3103","DOI":"10.1084\/jem.20071800","article-title":"Talin is required for integrin-mediated platelet function in hemostasis and thrombosis","volume":"204","author":"Petrich","year":"2007","journal-title":"J Exp Med"},{"issue":"12","key":"2020021108365580800_B27","doi-asserted-by":"crossref","first-page":"883","DOI":"10.1091\/mbc.1.12.883","article-title":"Affinity modulation of the alpha IIb beta 3 integrin (platelet GPIIb-IIIa) is an intrinsic property of the receptor","volume":"1","author":"O\u2019Toole","year":"1990","journal-title":"Cell Regul"},{"issue":"40","key":"2020021108365580800_B28","doi-asserted-by":"crossref","first-page":"28071","DOI":"10.1074\/jbc.274.40.28071","article-title":"The talin head domain binds to integrin beta subunit cytoplasmic tails and regulates integrin activation","volume":"274","author":"Calderwood","year":"1999","journal-title":"J Biol Chem"},{"issue":"13","key":"2020021108365580800_B29","doi-asserted-by":"crossref","first-page":"3113","DOI":"10.1084\/jem.20071827","article-title":"Loss of talin 1 in platelets abrogates integrin activation, platelet aggregation, and thrombus formation in vitro and in vivo","volume":"204","author":"Nieswandt","year":"2007","journal-title":"J Exp Med"},{"issue":"8","key":"2020021108365580800_B30","doi-asserted-by":"crossref","first-page":"2250","DOI":"10.1172\/JCI31024","article-title":"The antithrombotic potential of selective blockade of talin-dependent integrin alpha IIb beta 3 (platelet GPIIb-IIIa) activation","volume":"117","author":"Petrich","year":"2007","journal-title":"J Clin Invest"},{"issue":"9","key":"2020021108365580800_B31","doi-asserted-by":"crossref","first-page":"1354","DOI":"10.1091\/mbc.e12-09-0695","article-title":"Two modes of integrin activation form a binary molecular switch in adhesion maturation","volume":"24","author":"Lee","year":"2013","journal-title":"Mol Biol Cell"},{"issue":"10","key":"2020021108365580800_B32","doi-asserted-by":"crossref","first-page":"2294","DOI":"10.1111\/j.1538-7836.2010.03998.x","article-title":"What is vinculin needed for in platelets?","volume":"8","author":"Mitsios","year":"2010","journal-title":"J Thromb Haemost"}],"container-title":["Blood Advances"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/ashpublications.org\/bloodadvances\/article-pdf\/2\/18\/2358\/1629307\/advances020487.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"http:\/\/ashpublications.org\/bloodadvances\/article-pdf\/2\/18\/2358\/1629307\/advances020487.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,9,2]],"date-time":"2022-09-02T09:31:50Z","timestamp":1662111110000},"score":1,"resource":{"primary":{"URL":"https:\/\/ashpublications.org\/bloodadvances\/article\/2\/18\/2358\/15975\/Rap1-binding-to-the-talin-1-F0-domain-makes-a"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,9,21]]},"references-count":32,"journal-issue":{"issue":"18","published-print":{"date-parts":[[2018,9,25]]}},"URL":"https:\/\/doi.org\/10.1182\/bloodadvances.2018020487","relation":{},"ISSN":["2473-9529","2473-9537"],"issn-type":[{"value":"2473-9529","type":"print"},{"value":"2473-9537","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,9,21]]}}}