Titin Is Present in the Elastic Tethers That Connect Separating Anaphase Chromosomes in Crane‐Fly Spermatocytes

Elastic tethers connect telomeres of separating chromosomes in anaphase of animal cells. Immunofluorescence staining of titin in crane-fly spermatocytes, using 4 different antibodies, shows that the giant elastic protein titin seems to be a component of mitotic tethers: titin "strands" extend between separating chromosomes, connecting their telomeres, just as tethers do. Since titin is responsible for elastic forces in myofibrils, we suggest that titin is responsible for the backwards forces exerted on chromosome arms during anaphase.