HRGP在小麦抗寒锻炼过程中的变化及其与抗寒性的关系

强抗寒小麦品种(R-025、中品94-19、品83-1、品83-2、品83-3、米罗诺夫808)经抗寒锻炼后,其幼苗体内的游离脯氨酸、细胞壁结合的羟脯氨酸和糖蛋白含量发生了明显的变化.游离脯氨酸含量比未经抗寒锻炼处理时增加5～32倍,细胞壁结合的羟脯氨酸含量比对照增加1.77～2.17倍,糖蛋白含量比对照增加4.68～9.72倍,而不抗寒小麦品种(中国春、冬103)增加量较小.脯氨酸积累进程各个品种间差异比较大,品83-1、品83-2积累较快,抗寒锻炼第21d时达到最高峰,而R-025在第56d达到最高峰.脯氨酸含量与小麦品种抗寒性相关不显著(相关系数为0.3462),而羟脯氨酸含量、糖蛋白含量与小麦品种抗寒性相关显著,相关系数分别为0.6491和0.7039.从小麦细胞壁纯化得到了2种伸展蛋白Extensm1和Ex-tensin2,其含量都和小麦品种抗寒性呈正相关.Extensin1是分子量为28kD、羟脯氨酸为主要成份(32mo1%)的富含羟脯氨酸糖蛋白.

Changes of Hydroxyproline-rich Glycoprotein in Wheat under Cold Stress and Its Relationship to Cold Resistance

After cold hardening the content of free proline, hydroxyproline combined with cell wall, and glycoprotein changed obviously in wheat seedlings of strong cold resistant varieties R 025, Zhongpin 94 19, Pin 83 1, Pin 83 2, Pin 83 3, and Mironov 808. The accumulating process of proline varied in different varieties, and the correlation between proline content and cold resistance of wheat was not significant (correlation coefficient=0 3462). But both hydroxyproline and glycoprotein had a significant correlation with the cold resistance of wheat, and the correlation coefficients of them were 0 6491 and 0 7039, respectively. Two types of extensin protein, Extensin 1 and Extensin 2 were purified on a CM cellulose column, and they both had a positive relationship with the cold resistance of wheat. SDS PAGE and amino acids analysis demonstrated that Extensin 1 was a kind of hydroxyproline rich glycoprotein with a molecular weight of 28 kD, and hydroxyproline was the major component of it(32 mol%).