Positioning of gene products during Caulobacter cell differentiation.

Caulobacter crescentus has one of the simplest known developmental programs that exhibits both temporal and spatial organization. A hallmark of the Caulobacter cell cycle is that the progeny cells that result from each cell division differ from one another with respect to structure and developmental program. The process of establishing asymmetry prior to cell division requires that a number of gene products be targeted to a pole of the predivisional cell and consequently segregated to one of the two progeny. Several products involved in flagellar biogenesis and the chemotaxis machinery are segregated to the swarmer cell. Evidence suggests that the protein product of some fla and che genes is targeted to the incipient swarmer cell pole. In the case of other flagellar genes, it is the mRNA that is apparently segregated to the swarmer cell. Two heat shock proteins, DnaK and Lon are specifically segregated to the progeny stalked cell.