Long link induction between the microtubules of the manchette in intermediate stages of spermiogenesis

Summary

Links unusual for their length and variable morphology have been described between manchette microtubules in late stages of rat spermiogenesis. In earlier stages of rat spermiogenesis obvious links longer than ∼160 Å are rare, the majority being ∼80 or ∼120 Å in length. The most easily discernible geometric pattern in cross-sections of assemblies of manchette microtubules in intermediate stages of rat spermiogenesis is that of linear arrays sometimes resulting in long and irregularly folded chains of closely linked microtubules. Colcemid disrupts these arrays and is responsible for the formation of more complex geometric patterns. Six hours after drug administration the manchette is dramatically reduced in length. Sheet-like links of variable dimensions and >160 Å in length interconnect not only microtubules but C-type microtubules as well as other links. These links are similar in morphology to those found in later stages of rat spermiogenesis. It is suggested that the formation of these links may perhaps be dependent upon aspects of microtubule disassembly.