title: [Myr-RKEFAK Peptide Selectively Regulates Outside-in Signaling Transduction-related Functions in Human Platelets].
abstract: OBJECTIVE
  To study the effect of interaction of the talin rod domain integrin binding site 2 with integrin β3 on platelet signal transduction.
  
  
  METHODS
  A peptide that mimics the membrane proximal α helix 6 residues R724 KEFAK729 of the integrin β3 cytoplasmic tails was designed and synthesized, to which the myristoylation was covalently linked to the N-terminal of the peptide enabling membrane penetration. The effects of myr-RKEFAK peptide on the typical platelet outside-in signaling ovent (stable adhesion and spreading on immobilized fibrinogen, aggregation, fibrin clot retraction) and inside-out signaling events (soluble fibrinogen binding) were tested.
  
  
  RESULTS
  myr-RKEFAK peptide dose-dependently inhibited platelet stable adhesion and spreading on immobilized fibrinogen, irreversible aggregation, as well as fibrin clot retraction, but not soluble fibrinogen binding and reversible phase of platelet aggregation.
  
  
  CONCLUSIONS
  The cell-penetrating peptide myr-RKEFAK causes an inhibitory effect on integrin β3 outside-in signaling-regulated platelets functions, but did not affect inside-out signaling-regulated platelets functions.
authors.affiliation: State Key Laboratory of Meidical Genomics and Shanghai Institute of Hematology. Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China.
authors.forename: Zhang-Biao
authors.initials: ZB
authors.lastname: Long
authors.affiliation: State Key Laboratory of Meidical Genomics and Shanghai Institute of Hematology. Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China.
authors.forename: Jian-Song
authors.initials: JS
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Meidical Genomics and Shanghai Institute of Hematology. Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China.
authors.forename: Xiao-Feng
authors.initials: XF
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Meidical Genomics and Shanghai Institute of Hematology. Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China.
authors.forename: Ji-Chun
authors.initials: JC
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Meidical Genomics and Shanghai Institute of Hematology. Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Ruan
authors.affiliation: State Key Laboratory of Meidical Genomics and Shanghai Institute of Hematology. Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Xiao
authors.affiliation: State Key Laboratory of Meidical Genomics and Shanghai Institute of Hematology. Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, China. E-mail: xixiaodong@shsmu.edu.cn.
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Xi
mesh_terms: D001792:Blood Platelets; D005340:Fibrinogen; D006801:Humans; D039661:Integrin beta3; D010455:Peptides; D010973:Platelet Adhesiveness; D010974:Platelet Aggregation; D015398:Signal Transduction
chemical_list: D039661:Integrin beta3; D010455:Peptides; D005340:Fibrinogen