Docimo Teresa, Caruso Immacolata, Ponzoni Elena, Mattana Monica, Galasso Incoronata
Institute of Agricultural Biology and Biotechnology, CNR, Via Bassini 15, Milan 20133, Italy.
Institute of Agricultural Biology and Biotechnology, CNR, Via Bassini 15, Milan 20133, Italy.
Plant Physiol Biochem. 2014 Nov;84:142-148. doi: 10.1016/j.plaphy.2014.09.011. Epub 2014 Sep 24.
Globulins are the predominant class of seed storage proteins in a wide variety of plants. In many plant species globulins are present in several isoforms encoded by gene families. The major seed storage protein of Cannabis sativa L. is the globulin edestin, widely known for its nutritional potential. In this work, we report the isolation of seven cDNAs encoding for edestin from the C. sativa variety Carmagnola. Southern blot hybridization is in agreement with the number of identified edestin genes. All seven sequences showed the characteristic globulin features, but they result to be divergent members/forms of two edestin types. According to their sequence similarity four forms named CsEde1A, CsEde1B, CsEde1C, CsEde1D have been assigned to the edestin type 1 and the three forms CsEde2A, CsEde2B, CsEde2C to the edestin type 2. Analysis of the coding sequences revealed a high percentage of similarity (98-99%) among the different forms belonging to the same type, which decreased significantly to approximately 64% between the forms belonging to different types. Quantitative RT-PCR analysis revealed that both edestin types are expressed in developing hemp seeds and the amount of CsEde1 was 4.44 ± 0.10 higher than CsEde2. Both edestin types exhibited a high percentage of arginine (11-12%), but CsEde2 resulted particularly rich in methionine residues (2.36%) respect to CsEde1 (0.82%). The amino acid composition determined in CsEde1 and CsEde2 types suggests that these seed proteins can be used to improve the nutritional quality of plant food-stuffs.
球蛋白是多种植物中主要的种子贮藏蛋白类别。在许多植物物种中，球蛋白以基因家族编码的几种同工型存在。大麻的主要种子贮藏蛋白是球蛋白麻仁球蛋白，因其营养潜力而广为人知。在这项工作中，我们报道了从大麻品种卡马尼奥拉中分离出七个编码麻仁球蛋白的cDNA。Southern杂交结果与鉴定出的麻仁球蛋白基因数量一致。所有七个序列都显示出球蛋白的特征，但它们是两种麻仁球蛋白类型的不同成员/形式。根据它们的序列相似性，四种形式命名为CsEde1A、CsEde1B、CsEde1C、CsEde1D被归为麻仁球蛋白1型，三种形式CsEde2A、CsEde2B、CsEde2C被归为麻仁球蛋白2型。编码序列分析显示，同一类型的不同形式之间具有很高的相似性百分比（98 - 99%）, 而不同类型的形式之间则显著降低至约64%。定量RT-PCR分析表明，两种麻仁球蛋白类型在发育中的大麻种子中均有表达，且CsEde1的含量比CsEde2高4.44 ± 0.10。两种麻仁球蛋白类型都含有较高百分比的精氨酸（11 - 12%），但相对于CsEde1（0.82%），CsEde2的蛋氨酸残基特别丰富（2.36%）。CsEde1和CsEde2类型中确定的氨基酸组成表明，这些种子蛋白可用于改善植物食品的营养质量。
