title: Selenoprotein-transgenic Chlamydomonas reinhardtii.
abstract: Selenium (Se) deficiency is associated with the occurrence of many  diseases. However, excessive Se supplementation, especially with  inorganic Se, can result in toxicity. Selenoproteins are the major forms  of Se in vivo to exert its biological function. Expression of  those selenoproteins, especially with the application of a newly  developed system, is thus very important for studying the mechanism of  Se in nutrition. The use of Chlamydomonas reinhardtii (C. reinhardtii)  as a biological vector to express an heterogeneous protein is still at  the initial stages of development. In order to investigate the  possibility of using this system to express selenoproteins, human 15-KDa  selenoprotein (Sep15), a small but widely distributed selenoprotein in  mammals, was chosen for the expression platform test. Apart from the  wild-type human Sep15 gene fragment, two Sep15 recombinants were  constructed containing Sep15 open reading frame (ORF) and the  selenocysteine insertion sequence (SECIS) element from either human  Sep15 or C. reinhardtii selenoprotein W1, a highly expressed selenoprotein in this alga. Those Sep15-containing plasmids were transformed into C. reinhardtii CC-849 cells. Results showed that Sep15 fragments were successfully  inserted into the nuclear genome and expressed Sep15 protein in the  cells. The transgenic and wild-type algae demonstrated similar growth  curves in low Se culture medium. To our knowledge, this is the first  report on expressing human selenoprotein in green alga.
authors: Shenzhen Key Laboratory of Marine Biotechnology and Ecology, Department of Marine Biology, Shenzhen University, Shenzhen 518060, China. hqtdream2007@sina.com
authors: Qintang
authors: Q
authors: Hou
authors: Shi
authors: S
authors: Qiu
authors: Qiong
authors: Q
authors: Liu
authors: Jing
authors: J
authors: Tian
authors: Zhangli
authors: Z
authors: Hu
authors: Jiazuan
authors: J
authors: Ni
mesh_terms: D016825:Chlamydomonas reinhardtii / Q000235:genetics* / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000502:physiology; D018014:Gene Transfer Techniques; D006801:Humans; D030781:Organisms, Genetically Modified; D051140:Selenoproteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C495238:SELENOF protein, human; D051140:Selenoproteins