A developmentally regulated protein important for microtubule functions. Targets KAR3 to the cytoplasmic microtubules during mating. Essential for KAR3 function during prophase of meiosis I. Required for interhomolog recombination; synapsis of homologous chromosomes and establishment of a meiosis I spindle. {ECO:0000269|PubMed:10087265; ECO:0000269|PubMed:11729143}.