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Molecular genetic maps are commonly constructed by analyzing the segregation of restriction fragment length polymorphisms (RFLPs) among the progeny of a sexual cross. Here we describe a new DNA polymorphism assay based on the amplification of random DNA segments with single primers of arbitrary nucleotide sequence. These polymorphisms, simply detected as(More)
The ecmA (pDd63) and ecmB (pDd56) genes encode extracellular matrix proteins of the slime sheath and stalk tube of Dictyostelium discoideum. Using fusion genes containing the promoter of one or other gene coupled to an immunologically detectable reporter, we previously identified two classes of prestalk cells in the tip of the migrating slug; a central core(More)
The characteristic structure of the mature Dictyostelium culminant is created by the regionalized cellular differentiation and directed movement of prestalk cells. The front prestalk zone of the migratory slug has previously been considered to be a homogeneous tissue. Here we demonstrate, however, the existence of multiple classes of prestalk cells located(More)
The cAMP-dependent protein kinase (PKA) holoenzyme of Dictyostelium comprises a single regulatory (R) and catalytic (C) subunit, and both proteins increase in concentration during cellular aggregation. In order to determine the role of the kinase, we have constructed mutants of the R subunit that are defective in cAMP binding, in inhibition of the C(More)
The TTGA-binding factor is a transcriptional regulator activated by DIF, the chlorinated hexaphenone that induces prestalk cell differentiation in Dictyostelium. The same activity also functions as a repressor, controlling stalk cell differentiation. We show that the TTGA-binding factor is a STAT protein. Like the metazoan STATs, it functions via the(More)
A population of Arabidopsis thaliana recombinant inbred lines was constructed and used to develop a high-density genetic linkage map containing 252 random amplified polymorphic DNA markers and 60 previously mapped restriction fragment length polymorphisms. Linkage groups were correlated to the classical genetic map by inclusion of nine phenotypic markers in(More)
Expression of a dominant inhibitor of the Dictyostelium cAMP-dependent protein kinase in prespore cells blocks their differentiation into spore cells. The resultant structures comprise a normal stalk supporting a bolus of cells that fail to express a sporulation-specific gene and that show greatly reduced levels of expression of several prespore-specific(More)
The ecmA gene of Dictyostelium encodes an extracellular matrix protein and is selectively expressed in prestalk cells. We show that its promoter contains discrete elements that direct expression in different subpopulations of prestalk cells. Prestalk(pst)A cells occupy the front half of the prestalk region. Expression in pstA cells requires DNA sequences(More)
We placed a specific inhibitor of cyclic AMP-dependent protein kinase (PKA) under the control of a prestalk-specific promoter. Cells containing this construct form normally patterned slugs, but under environmental conditions that normally trigger immediate culmination, the slugs undergo prolonged migration. Slugs that eventually enter culmination do so(More)
Dd-STAT, the protein that in part controls Dictyostelium stalk cell differentiation, is a structural and functional homolog of metazoan signal transducers and activators of transcription (STATs). Although present during growth and throughout development, Dd-STAT's tyrosine phosphorylation and nuclear localization are developmentally and spatially regulated.(More)