Methods for gentle, differential heating of part of a single living cell

The fabrication and use of resistance wire microheaters is described and the results obtainable with cells are illustrated. The microheaters permit localized warming of a small area, wherever desired, within a single living cell. This is directly shown by the production of localized structural changes in the mitotic spindle. Thus in this case, subcellular areas respond independently to the local temperature. The method is applicable to a variety of cellular processes, providing clues to cellular control mechanisms.