渗调蛋白(osmotin,OSM)是植物中普遍存在的多功能蛋白,研究己明确OSM是胁迫响应蛋白,由参与胁迫响应的功能推测,OSM通过参与生长发育,调控植物对胁迫的响应,但OSM参与生长发育的研究报道极为有限。本研究在分离了马铃薯(Solanum tuberosum)StOSM-3b基因cDNA的基础上,用pCambia1305.35S载体,通过基因工程技术,构建了抑制渗调蛋白表达的反义StOSM-3b基因cDNA载体,农杆菌(Agrobacteriumtumefaciens)介导途径转化反义StOSM-3b至马铃薯体内,筛选获得B.葡萄糖苷酸酶(B—glucuronidase,GUS)染色阳性转化株系,阳性株系叶片StOSM-3bmRNA积累和渗调蛋白酶联免疫吸附测定(enzyme linked immunosorbent assay,ELISA)定量数据分析显示,抑制株系叶片StOSM-3bmRNA积累是对照的25%,渗调蛋白含量是对照株系的52%,这表明反义StOSM-3b部分抑制了StOSM.3b表达,下调了马铃薯渗调蛋白的体内积累;下调渗调蛋白表达株系表现为生长缓慢、个体矮小、且生育期显著缩短、不能正常结薯的表型,且生长节奏失调。该研究结果为渗调蛋白参与生长和发育过程提供了直接证据。
Osmotin (OSM) is a multifunction protein present in wide plant species. It is inferred that OSM regulates plant adaption to stress through involving in plant growth and development, However, direct evidence linking between OSM and growth is rare. Based on StOSM-3b cDNA of potato (Solanum tuberosum) isolated in previous study, an antisense StOSM-3b vector, aiming to inhibit OSM expression, was constructed in this study. The antisense StOSM-3b was transformed into potato by Agrobacterium-mediated approach. A positive transgenic line was screened by β- glucuronidase (GUS) staining. Analysis on data assayed showed that accumulations of StOSM-3b mRNA and OSM contents by enzyme linked immunosorbent assay (ELISA) in the transgenic potato leafs was 25% and 52% of that in control, respectively. This indicated that the antisense StOSM-3b partially inhibited expression of StOSM-3b and down-regulated OSM accumulation in the transgenic potato. OSM down-expression led to a tardy growth, dwarfing and no tuber-formation phenotype with disorder in growth rhythm. The results provide a direct evidence to indicate that osmotin involves in plant growth and development.