...Péter Kovács; György Csaba The unicellular Tetrahymena enzymatically split the synthetic phosphodiester, 4-methylum-belliferyl phosphocoline substrate. The enzyme activity was completely blocked in vitro and drastically inhibited in vivo by G-protein activating fluorides (NaF; AlF 4 – and BeF 3...

...Hargita Hegyesi; Cs. Szalai; A. Falus; G. Csaba RNA was isolated from Tetrahymena pyriformis GL and using human histidine decarboxylase (HDC) gene primers, the RT-PCR product was sequenced. A fraction containing 207 base pairs was compared to the published sequences of prokaryotic and mammalian...

...G. Csaba; P. Kovács Proline-glycine, proline-leucine and proline-valine dipeptides and their retro variants were used in the experiments to study the effects of pretreatment (imprinting) in Tetrahymena, by investigating fluorescein isothiocyanate (FITC)-conjugated peptide binding. The protozoan...

...L. Köhidai; P. Kovács; G. Csaba Chemotactic properties of amino acids (L-alanine, glycine and L-lysine) and their oligopeptides (10 −6 M) and binding sites to these ligands were investigated in two unicellular models, the heterotrophic Tetrahymena pyriformis and the auxotrophic Dunaliella salina...

...A. K. Fülöp; G. Csaba Gold-labeled insulin is bound first of all to the cilia of the oral field of Tetrahymena. A primary treatment (hormonal imprinting) with insulin increases the binding capacity even after 24h and makes it more sensitive for appearance a week later, within a minute of giving...

...P. Kovács; G. Csaba The unicellular tetrahymena contains inositol phospholipids (PI, PIP, PIP 2 ) and GPIs. Treatment with 10 −5 M insulin decreases the total 3 H-inositol incorporation and incorporation into PI. 24 h after 10 −6 M insulin treatment there is an elevation of these parameters. Second...

...G. Csaba; Hargita Hegyesi The unicellular Tetrahymena possess hormone receptors in the nuclear envelope similarly to higher rank animals. These receptors bind insulin and their specificity is detectable by monoclonal antibodies developed to insulin. The hormonal (insulin) pretreatment (imprinting...

...A. K. Fülöp; G. Csaba Tritiated diazepam accumulates mainly in the mitochondria of the unicellular Tetrahymena. This is the case in both a single (the first encounter) and a repeated (one day or a week after the first) administration of the drug. When imprinting of Tetrahymena by diazepam...

...G. Csaba; Zsuzsa Darvas Histamine increased specifically the phagocytic activity of the unicellular Tetrahymena, whereas insulin had no influence on it. Insulin antagonized the phagocytosis stimulating action of histamine after simultaneous exposure and after preexposure two days earlier as well...

...G. Csaba; P. Kovács Insulin and its A and B chain increased the quantity of intracellular PAS-positive material (glycogen) in tetrahymena, whereas the combined A+B chains decreased it. Imprinting—previous interaction—with insulin, its A and B chains in themselves and with the A+B chain increased...

...P. Kovács; Y. Nozawa; G. Csaba Studies based on treatment with antibodies to thyrotropic hormone, luteotropic hormone, growth hormone or adrenocorticotropic hormone have shown that although the unicellular Tetrahymena does not possess sui generis receptors to all polypeptide hormones, such binding...

...Zsuzsa Darvas; Y. Nozawa; G. Csaba Of the L and D configurations of four amino acids (phenylalanine, valine, tryptophan, tyrosine) tested for influence on the growth rate of Tetrahymena, only L-tyrosine was able to induce imprinting in Tetrahymena pyriformis Zeuthen. D-valine stimulated...