title: Enhancement of mouse sperm motility by trophinin-binding peptide.
abstract: BACKGROUND
  Trophinin is an intrinsic membrane protein that forms a complex in the cytoplasm with bystin and tastin, linking it microtubule-associated motor dynein (ATPase) in some cell types. Previously, we found that human sperm tails contain trophinin, bystin and tastin proteins, and that trophinin-binding GWRQ (glycine, tryptophan, arginine, glutamine) peptide enhanced motility of human sperm.
  
  
  METHODS
  Immunohistochemistry was employed to determine trophinin protein in mouse spermatozoa from wild type mouse, by using spermatozoa from trophinin null mutant mice as a negative control. Multivalent 8-branched GWRQ (glycine, tryptophan, arginine, glutamine) peptide or GWRQ-MAPS, was chemically synthesized, purified by HPLC and its structure was confirmed by MALDI-TOF mass spectrometry. Effect of GWRQ-MAPS on mouse spermatozoa from wild type and trophinin null mutant was assessed by a computer-assisted semen analyzer (CASA).
  
  
  RESULTS
  Anti-trophinin antibody stained the principal (central) piece of the tail of wild type mouse sperm, whereas the antibody showed no staining on trophinin null sperm. Phage particles displaying GWRQ bound to the principal piece of sperm tail from wild type but not trophinin null mice. GWRQ-MAPS enhanced motility of spermatozoa from wild type but not trophinin null mice. CASA showed that GWRQ-MAPS enhanced both progressive motility and rapid motility in wild type mouse sperm.
  
  
  CONCLUSIONS
  Present study established the expression of trophinin in the mouse sperm tail and trophinin-dependent effect of GWRQ-MAPS on sperm motility. GWRQ causes a significant increase in sperm motility.
authors.affiliation: Tumor Microenvironment Program, Cancer Center, Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA.
authors.forename: Seong Kyu
authors.initials: SK
authors.lastname: Park
authors.forename: Jiwon
authors.initials: J
authors.lastname: Yoon
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.forename: Toshiaki K
authors.initials: TK
authors.lastname: Shibata
authors.forename: Khatereh
authors.initials: K
authors.lastname: Motamedchaboki
authors.forename: Kyung Jun
authors.initials: KJ
authors.lastname: Shim
authors.forename: Mun Seog
authors.initials: MS
authors.lastname: Chang
authors.forename: Seung Ho
authors.initials: SH
authors.lastname: Lee
authors.forename: Naoaki
authors.initials: N
authors.lastname: Tamura
authors.forename: Shingo
authors.initials: S
authors.lastname: Hatakeyama
authors.forename: Daita
authors.initials: D
authors.lastname: Nadano
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Sugihara
authors.forename: Michiko N
authors.initials: MN
authors.lastname: Fukuda
mesh_terms: D000818:Animals; D015815:Cell Adhesion Molecules / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D010455:Peptides / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D011485:Protein Binding / Q000502:physiology; D013081:Sperm Motility / Q000502:physiology*; D015854:Up-Regulation / Q000502:physiology*
chemical_list: D015815:Cell Adhesion Molecules; D010455:Peptides; C445321:trophinin, mouse