Stomatal resistances and turgor pressures were measured during a 12-day period on leaves of bean (Phaseolus vulgaris L. cv. Contender) which were treated with kinetin, were salinized or were treated with kinetin and salinized. Stomatal resistances were highest in salt-stressed plants, and progressively lower in salt-stressed and kinetin-treated plants, control plants, and kinetin-treated plants...

The effects of kinetin on starch and sugar levels and on (14)CO(2) and (32)P-orthophosphate labeling patterns of floated Chinese cabbage (Brassica pekinensis) leaf discs were investigated. Kinetin caused gross starch degradation. Neutral sugars were depressed by 30 to 40% in leaf tissue treated with kinetin for 24 hours. (14)CO(2) labeling of leaf discs pretreated with kinetin for 24 hours show...

Kinetin at physiological concentrations causes significant reduction of GA3-promoted growth in excised Avena stem segments. Kinetin is therefore considered to be a gibberellinantagonist in this system. A Eineweaver-Burke plot reveals that kinetin acts non-competitively with GAa. The kinetin inhibition of GA3-promoted growth can be seen within 6 hours. It was found that soluble protein is marked...

The effect of kinetin on the de novo formation of thiamine in tobacco callus cultures was measured by following the isotope dilution of previously introduced (14)C-thiamine. Thiamine was determined by the thiochrome fluorescence assay after chromatographic purification. Morphological effects induced by high kinetin concentrations were visible within a week after tissue transfer, but thiamine sy...

Modulating key dynamics of plant growth and development, the effects of the plant hormone cytokinin on animal cells gained much attention recently. Most previous studies on cytokinin effects on mammalian cells have been conducted with elevated cytokinin concentration (in the μM range). However, to examine physiologically relevant dose effects of cytokinins on animal cells, we systematically ana...

BACKGROUND Kinetin is a plant hormone that regulates growth and differentiation. Keratinocytes, the basic building blocks of the epidermis, function in maintaining the skin barrier. OBJECTIVE We examined whether kinetin induces skin barrier functions in vitro and in vivo. METHODS To evaluate the efficacy of kinetin at the cellular level, expression of keratinocyte differentiation markers wa...

Partly dehydrated tobacco leaf tissue (Nicotiana rustica), stripped of the lower epidermis, was used to study the effect of kinetin on the rate of rehydration. Depending on the rate of rehydration in untreated tissue, kinetin either increased or decreased rehydration rates. The response to kinetin was very rapid and could be discerned in less than 2 minutes. On extensive dehydration, the tissue...

Kinetin and naphthaleneacetic acid were applied separately and in combination to excised leaf disks, localized areas of laminae, and petioles of detached leaves of broccoli (Brassica oleracea L., var. italica) and Xanthium (Xanthium pensylvanicum Wallr.). Senscence (measured as loss of chlorophyll) was strongly retarded by kinetin, but very slightly influenced by naphthaleneacetic acid. When th...

Kinetin and kinetin ribofuranoside have been tested on tissue cultures of adult human skin, breast carcinomas, and cystic disease of the breast. Outgrowths of epi thelium from skin cultures were retarded by kinetin and completely inhibited by kinetin ribofuranoside when treated with 1.0 mg. per cent. A concentration of 0.1 mg. per cent of kinetin had no effect on the extent or population of cel...

A comparative study was made of the effects of auxin (alpha-naphthalene acetic acid), kinetin (6-furfurylaminopurine) and a mixture of auxin and kinetin applied in vivo on synthesis of RNA and protein and the distribution of such synthesis amongst the subcellular fractions of sections of endocarp from Kentucky Wonder pole beans (Phaseolus vulgaris, L.). Auxin caused considerable enhancement of ...