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H Schaller

Publications and source records attributed to H Schaller.

23 records · Page 2Linked to original sources
PubMed1975

Stabilization of promoter complexes with a single ribonucleoside triphosphate.

Under specific binding conditions RNA polymerase forms complexes at several sites of the replicative form DNA of bacteriophage fd. One of these complexes becomes stable to both high salt and low temperature after incubation with GTP. None of the complexes is stabilized by ATP. The stabilization by GTP results from the synthesis of an oligo(G) chain, which is bound in the complex. Size and pyrimidine fingerprints of the DNA segment protected by the enzyme against digestion with DNase are not changed upon initiation of oligo(G) synthesis. This result indicates that binding site and initiation site are identical parts of a promoter region.

Binding Sites↗
PubMed1975

Initiation of transcription within an RNA-polymerase binding site.

1. The 5'-terminal sequence of the RNA transcribed from bacteriophage fd replicative form DNA under the control of promotor region I has been determined to be ppp(Gp)nUpApApApGpApCpCpUpGpApUpUp. . . 2. This sequence is complementary to the 5'-terminal sequence of the minus strand of the corresponding RNA polymerase binding site I, the starting point for RNA synthesis lying approximately in the middle of the binding site. 3. This initial sequence is also transcribed faithfully from isolated complexes of RNA polymerase and binding site I, obtained by DNase digestion of complexes between RNA polymerase and fd replicative form DNA. These highly stable complexes can not be reconstituted from binding site and enzyme. 4. It is concluded that RNA polymerase binding site and initiation site are identical parts of a promoter region, and that no "drift" between these sites is required as a step in RNA chain initiation. An additional non-transcribed outside region is implicated as essential for full promoter function.

Base Sequence↗
PubMed1975

Nucleotide sequence of an RNA polymerase binding site from the DNA of bacteriophage fd.

The primary structure of a strong RNA polymerase binding site in the replicative form DNA of phage fd has been determined by direct DNA sequencing. It is: (see article). The molecule contains regions with 2-fold symmetry and sequence homologies to promoter regions from other DNAs. The startpoint of transcription is located in the center of the binding site.

Base Sequence↗
PubMedDate not supplied

Heat, cold and inflammation.

Although therapeutic heat and cold measures are widely used in rheumatic diseases, their application in joint inflammations is still broadly empirical. Animal experiments concerning the effects of systemic hyperthermia and of local heat and cold applications upon experimentally induced inflammations (dextran edema, formol edema, kaolin edema, carrageenan edema, adjuvant arthritis) show that some inflammations are significantly depressed, i.e. they are effected by a useful therapeutic influence, but that cold and heat can also act as enhancing inflammatory stimulus. Under certain conditions, whole-body hyperthermia has immuno-suppressive effects. Although the exact points of intervention of heat and cold investigations, acute exsudative inflammations seem to be better influenced by cold; on the contrary, chronic torpid and proliferous inflammations are better influenced by heat. Prostaglandin mediated inflammations can be aggravated by cold, because it stimulates the prostaglandin synthesis; acute exsudative inflammatory processes are most often aggravated by heat. These results show that both therapeutic agents should be applied within a well-defined range and with care.

Animals↗