caa a22 4500 445841338 CHVBK 20180317145345.0 cr unu---uuuuu 170323e20110401xx s 000 0 eng 10.1007/s10725-010-9529-y doi (NATIONALLICENCE)springer-10.1007/s10725-010-9529-y Effects of day length, light quality and ethylene on PHYTOCHROME B expression during stem elongation in Stellaria longipes [Elektronische Daten] [Wenze Li, Zihong Song, R. Neil Emery, C. Chinnappa] The prairie ecotype of Stellaria longipes (Caryophyllaceae) is highly responsive to light and is a shade avoider. Using the prairie ecotype as a model, we investigated the expression of the PHYTOCHROME B (PHYB) gene in response to different ratios of red to far-red light (R/FR), photoperiods and ethephon, an ethylene producing compound. This was done to examine the potential role of the PHYB and its interaction with ethylene in determining the plasticity of stem elongation. The PHYB gene was constitutively expressed in flowers, leaves, stems, and roots. The relative transcript abundance of the PHYB gene increased significantly upon transfer of etiolated-seedlings to light. The level of the PHYB gene transcript under elevated R/FR (3.5) was significantly higher than that under lower R/FR (0.7) in de-etiolated-mature plants. Long day photoperiod (16h light/day, LD) significantly promoted stem growth, whereas plants under short day photoperiod (8h light/day, SD) showed minor elongation. Interestingly, under LD, but not under SD, the level of PHYB mRNA significantly correlated with stem elongation. The plants treated with high concentration of ethephon (10.0molm−3) showed a 55% decrease in PHYB transcript within the first 4days after treatment, and the level of PHYB transcript was significantly lower than that in control plants and the plants treated with a lower concentration of ethephon (0.1molm−3). Taken together with our earlier studies related to stem elongation, our results suggest that the level of PHYB gene transcription on day 4 is critical for the initiation of stem elongation. After this stage, a relatively high level of the PHYB gene transcription might be important for maintaining stem elongation of the prairie plants of S. longipes. Springer Science+Business Media B.V., 2010 Ethephon nationallicence Phenotypic plasticity nationallicence Photoperiod nationallicence Phytochrome B nationallicence Stem elongation nationallicence Stellaria longipes nationallicence Li Wenze Department of Biological Sciences, University of Calgary, 2500 University Dr. N.W, T2N 1N4, Calgary, AB, Canada aut Song Zihong Department of Biological Sciences, University of Calgary, 2500 University Dr. N.W, T2N 1N4, Calgary, AB, Canada aut Neil Emery R. Biology Department, Trent University, 1600 West Bank Drive, K9J 7B8, Peterborough, ON, Canada aut Chinnappa C. Department of Biological Sciences, University of Calgary, 2500 University Dr. N.W, T2N 1N4, Calgary, AB, Canada aut Plant Growth Regulation Springer Netherlands 63/3(2011-04-01), 291-300 0167-6903 63:3<291 2011 63 10725 https://doi.org/10.1007/s10725-010-9529-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10725-010-9529-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Li Wenze Department of Biological Sciences, University of Calgary, 2500 University Dr. N.W, T2N 1N4, Calgary, AB, Canada aut NATIONALLICENCE 700 1- Song Zihong Department of Biological Sciences, University of Calgary, 2500 University Dr. N.W, T2N 1N4, Calgary, AB, Canada aut NATIONALLICENCE 700 1- Neil Emery R. Biology Department, Trent University, 1600 West Bank Drive, K9J 7B8, Peterborough, ON, Canada aut NATIONALLICENCE 700 1- Chinnappa C. Department of Biological Sciences, University of Calgary, 2500 University Dr. N.W, T2N 1N4, Calgary, AB, Canada aut NATIONALLICENCE 773 0- Plant Growth Regulation Springer Netherlands 63/3(2011-04-01), 291-300 0167-6903 63:3<291 2011 63 10725 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer