Ceasar S Antony, Hodge Angela, Baker Alison, Baldwin Stephen A
Centre for Plant Sciences and School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom.
Department of Biology, University of York, Wentworth Way, York, United Kingdom.
PLoS One. 2014 Sep 24;9(9):e108459. doi: 10.1371/journal.pone.0108459. eCollection 2014.
Phosphorus (P) is an essential element which plays several key roles in all living organisms. Setaria italica (foxtail millet) is a model species for panacoid grasses including several millet species widely grown in arid regions of Asia and Africa, and for the bioenergy crop switchgrass. The growth responses of S. italica to different levels of inorganic phosphate (Pi) and to colonisation with the arbuscular mycorrhizal fungus Funneliformis mosseae (syn. Glomus mosseae) were studied. Phosphate is taken up from the environment by the PHT1 family of plant phosphate transporters, which have been well characterized in several plant species. Bioinformatic analysis identified 12 members of the PHT1 gene family (SiPHT1;1-1;12) in S. italica, and RT and qPCR analysis showed that most of these transporters displayed specific expression patterns with respect to tissue, phosphate status and arbuscular mycorrhizal colonisation. SiPHT1;2 was found to be expressed in all tissues and in all growth conditions tested. In contrast, expression of SiPHT1;4 was induced in roots after 15 days growth in hydroponic medium of low Pi concentration. Expression of SiPHT1;8 and SiPHT1;9 in roots was selectively induced by colonisation with F. mosseae. SiPHT1;3 and SiPHT1;4 were found to be predominantly expressed in leaf and root tissues respectively. Several other transporters were expressed in shoots and leaves during growth in low Pi concentrations. This study will form the basis for the further characterization of these transporters, with the long term goal of improving the phosphate use efficiency of foxtail millet.
磷（P）是一种必需元素，在所有生物中都发挥着几个关键作用。粟（狗尾草）是黍族禾本科植物的模式物种，包括在亚洲和非洲干旱地区广泛种植的几种粟类物种，也是生物能源作物柳枝稷的模式物种。研究了粟对不同水平无机磷酸盐（Pi）以及与丛枝菌根真菌摩西管柄囊霉（同义词：摩西球囊霉）共生的生长响应。植物磷酸盐转运蛋白的PHT1家族从环境中吸收磷酸盐，该家族在几种植物物种中已得到充分表征。生物信息学分析在粟中鉴定出12个PHT1基因家族成员（SiPHT1;1 - 1;12），RT和qPCR分析表明，这些转运蛋白中的大多数在组织、磷酸盐状态和丛枝菌根定殖方面表现出特定的表达模式。发现SiPHT1;2在所有测试的组织和所有生长条件下均有表达。相比之下，在低Pi浓度水培介质中生长15天后，SiPHT1;4在根中的表达被诱导。SiPHT1;8和SiPHT1;9在根中的表达通过摩西管柄囊霉的定殖被选择性诱导。发现SiPHT1;3和SiPHT1;4分别主要在叶和根组织中表达。在低Pi浓度生长期间，其他几种转运蛋白在地上部和叶中表达。这项研究将为进一步表征这些转运蛋白奠定基础，长期目标是提高粟的磷酸盐利用效率。
