Essential factor for meiotic homologous chromosome pairing (synapsis) (PubMed:14758540). Plays an essential role in promoting homologous chromosome synapsis. Does not seem to play a role in chromosomal axial element formation, sister chromatid cohesion at centromeres or kinetochore assembly in meiosis I (PubMed:16410547). During interphase-early leptotene, distributed as numerous punctuate foci throughout the chromatin. Associates with chromosomal axes at leptotene and zygotene (PubMed:16410547, PubMed:21119003). Associates with chromosomal axes at zygotene (PubMed:27436711). Removed from the axes of arm regions when homologous chromosomes have been synapsed (PubMed:16410547, PubMed:21119003). Localizes to centromeres until diakinesis (PubMed:16410547). Expressed in anthers and ovules. Failure of the pairing of homologous chromosomes during meiosis (asynapsis or non-homologous synapsis) in both male and female gametophytes. May be due to a competing acceptor splice site.