Chojnacka Magdalena, Szewińska Joanna, Mielecki Marcin, Nykiel Małgorzata, Imai Ryozo, Bielawski Wiesław, Orzechowski Sławomir
Department of Biochemistry, Faculty of Agriculture and Biology, Warsaw University of Life Sciences - SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland.
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland.
J Plant Physiol. 2015 Feb 1;174:161-5. doi: 10.1016/j.jplph.2014.09.014. Epub 2014 Oct 16.
Water-deficit is accompanied by an increase in proteolysis. Phytocystatins are plant inhibitors of cysteine proteinases that belong to the papain and legumain family. A cDNA encoding the protein inhibitor TrcC-8 was identified in the vegetative organs of triticale. In response to water-deficit, increases in the mRNA levels of TrcC-8 were observed in leaf and root tissues. Immunoblot analysis indicated that accumulation of the TrcC-8 protein occurred after 72h of water-deficit in the seedlings. Using recombinant protein, inhibitory activity of TrcC-8 against cysteine proteases from triticale and wheat tissues was analyzed. Under water-deficit conditions, there are increases in cysteine proteinase activities in both plant tissues. The cysteine proteinase activities were inhibited by addition of the recombinant TrcC-8 protein. These results suggest a potential role for the triticale phytocystatin in modulating cysteine proteinase activities during water-deficit conditions.
水分亏缺伴随着蛋白水解作用的增强。植物胱抑素是属于木瓜蛋白酶和豆天冬酰胺酶家族的半胱氨酸蛋白酶的植物抑制剂。在小黑麦的营养器官中鉴定出了一个编码蛋白抑制剂TrcC-8的cDNA。响应水分亏缺，在叶片和根组织中观察到TrcC-8的mRNA水平升高。免疫印迹分析表明，在水分亏缺72小时后，幼苗中出现了TrcC-8蛋白的积累。使用重组蛋白，分析了TrcC-8对小黑麦和小麦组织中半胱氨酸蛋白酶的抑制活性。在水分亏缺条件下，两种植物组织中的半胱氨酸蛋白酶活性均升高。添加重组TrcC-8蛋白可抑制半胱氨酸蛋白酶的活性。这些结果表明小黑麦植物胱抑素在水分亏缺条件下调节半胱氨酸蛋白酶活性方面具有潜在作用。
