..., whereas most of the posterior zone consists of prespore cells. We now present evidence that the cAMP-dependent protein kinase (PKA) and the RING domain/leucine zipper protein rZIP interact genetically to mediate a transcriptional activation gradient that regulates the differentiation of prespore cells...

... kinase ATPases protein kinases cytoplasmic streaming polarized growth Calcium injected into cytoplasm has very limited mobility. This may be the consequence of efficient internal sequestration systems which may include calcium-binding proteins bound to the cytoskeleton. A localized stimulus...