恭賀!!!

中山大學與中央研究院合作之海洋生科技博士學位學程學生 許媛婷 研究成果Nitric Oxide Up-regulates the Expression of Methionine Sulfoxide Reductase Genes in the Intertidal Macroalga Ulva fasciata for High Light Acclimation 被Plant Cell Physiology 接受，約在101年1 月初 on-line publication (Plant Cell Physiology 是SCIE Plant Science 類別187種期刊的第15名，排名約8%左右)

這是全世界第一次證實Nitric Oxide (NO) 可調控植物methionine sulfoxide reductase 基因表現，尤其是以大型海藻為材料，相信未來會被引用於高等植物研究

Nitric Oxide Up-regulates the Expression of Methionine Sulfoxide Reductase Genes in the Intertidal Macroalga Ulva fasciata for High Light Acclimation

Yuan-Ting Hsu and Tse-Min Lee 

Institute of Marine Biology, National Sun Yat-sen University, Kaohsiung 80424, Taiwan

Doctor Degree Program in Marine Biotechnology, National Sun Yat-sen University/Academia Sinica, Kaohsiung 80424, Taiwan

The Asia-Pacific Ocean Research Center, National Sun Yat-sen University, Kaohsiung 80424, Taiwan

Abstract

Nitric oxide (NO) has emerged as a fundamental signal molecule involving in the responses of plant to stress. A role of NO in the regulation of methionine sulfoxide reductase (MSR) mRNA expression and high light acclimation was studied in a green macroalga Ulva fasciata Delile. A transfer from darkness to high light (≥ 1,200 mmol photons·m^-2·s^-1) inhibited photosynthesis and growth but increased NO production and UfMSRA and UfMSRB transcripts. Trreatment of an NO scavenger, 2-(4-carboxy- phenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide (cPTIO), in 1,200 mmol photons·m^-2·s^-1 condition caused a further growth inhibition accompanied by an inhibition of the increase of UfMSRA and UfMSRB transcripts by high light, while the treatment of an NO generator, sodium nitroprusside (SNP), alleviated growth inhibition and enhanced UfMSRA and UfMSRB expression. An exposure to moderate light (300 mmol photons·m^-2·s^-1) condition also increased UfMSRA and UfMSRB transcripts, which were not affected by cPTIO treatment but enhanced by SNP treatment. So, NO does not mediate the up-regulation of UfMSR by a transfer to moderate light possibly as a pre-caution mechanism in the sense of increasing light intensities in the daytime. In conclusion, NO production can be induced in U. fasciata upon exposure to high light for up-regulation of UfMSRA and UfMSRB expression but the level of NO production is not sufficient for acquisition of full tolerance to high light stress. Enhanced NO production by exogenously applied NO generator can effectively trigger high light acclimation process, including UfMSRA and UfMSRB expression.

Keywords: acclimation • high light • methionine sulfoxide reductase • nitric oxide • Ulva fasciata