Analysis of insect holocentric chromosomes by atomic force microscopy.

In order to go in depth into the analysis of holocentric chromosome structure, atomic force microscopy (AFM) was applied to metaphase plates of the aphid Megoura viciae. AFM showed that aphid chromatids adhere to one another without any prominent structure detectable between them and without any evidence of chromosomal constrictions. AFM thus provided new and reliable evidences at a nanomolecular level concerning the holocentric structure of aphid chromosomes, without any of the artefacts due to sample staining or coating that are usually associated with electron microscopy.