Macaque sperm release ESP13.2 and PSP94 during capacitation: The absence of ESP13.2 is linked to sperm-zona recognition and binding

Theodore L Tollner, Ashley I. Yudin, Cathy A. Treece, James W. Overstreet, Gary N. Cherr

Research output: Contribution to journalArticlepeer-review

50 Scopus citations


ESP13.2 coats the entire surface of macaque sperm and remains until sperm become capacitated (Yudin et al., 2003: Biol Reprod 69: 1118-1128). Capacitation of macaque sperm is synchronized by treatment with dibutyrl cAMP (dbcAMP) and caffeine. ESP13.2 and PSP94 constituted ∼95% of the proteins released from the sperm surface following treatment with caffeine + dbcAMP. Caffeine and dbcAMP alone induce different patterns of ESP13.2 release. As determined by ELISAs of supernatants and immuno-fluorescent labeling of sperm heads, caffeine alone and caffeine + dbcAMP induced comparable release of ESP13.2, while dbcAMP-treated sperm did not differ from controls. Sperm treated with caffeine + dbcAMP showed a reduction of ESP13.2 from the entire surface, while caffeine treatment alone induced removal of ESP13.2 from the sperm head and midpiece. As confirmed with immunofluorescence, ESP13.2 could be added back to the surfaces of sperm that had been previously exposed to caffeine. Treatment with caffeine significantly increased the number of sperm that bound tightly to the zona pellucida as compared with controls (42 ± 9 and 13 ± 3 sperm/zona, respectively; P ≤ 0.01). This increase in binding was inhibited by "adding back" ESP13.2 to the sperm surface (12.8 ± 3; P ≤ 0.01). Alexa-conjugated anti-ESP13.2 Ig labeling of live sperm showed that only sperm lacking ESP13.2 over the head were capable of tight binding to the zona. Our results suggest that ESP13.2 masks zona pellucida ligands on the sperm surface and its release, as part of capacitation, is required for sperm-zona interaction.

Original languageEnglish (US)
Pages (from-to)325-337
Number of pages13
JournalMolecular Reproduction and Development
Issue number3
StatePublished - Nov 2004


  • Caffeine
  • dbcAMP
  • ESP13.2
  • Macaque sperm
  • Zona pellucida

ASJC Scopus subject areas

  • Genetics
  • Developmental Biology
  • Cell Biology


Dive into the research topics of 'Macaque sperm release ESP13.2 and PSP94 during capacitation: The absence of ESP13.2 is linked to sperm-zona recognition and binding'. Together they form a unique fingerprint.

Cite this