Verdugo-Perales Mercedes, Velez-de la Rocha Rosabel, León-Félix Josefina, Osuna-Enciso Tomas, Heredia José B, Osuna-Castro Juan A, Islas-Osuna Maria A, Sañudo-Barajas J Adriana
Laboratorio de Bioquímica Vegetal, Centro de Investigación en Alimentación y Desarrollo, A.C-Unidad Culiacán, Carret. a Eldorado km 5.5, Campo El Diez, 80110 Culiacán, Sinaloa Mexico.
Instituto de Investigación Lightbourn A.C. Carretera Las Pampas Km. 2.5 Col. Tierra y Libertad, Cd. Jiménez, 33980 Chihuahua, Mexico.
3 Biotech. 2018 Jan;8(1):5. doi: 10.1007/s13205-017-1031-z. Epub 2017 Dec 8.
Lysine-rich (Lys-rich) proteins encoded by , , and genes are cell wall-associated glycopeptides related to sexual reproduction in flowering plants. This subclass belongs to classical arabinogalactan proteins (AGPs) widely studied in model plants like . In this study, we identified the cDNA from bell pepper ( L.), as well as its expression pattern during vegetative and reproductive development. The deduced amino acid sequence revealed a Lys-rich AGP18 protein of 238 amino acids residues in length with an estimated molecular mass of 22.85 kDa and an isoelectric point of 9.7. The protein is predicted as canonical AGP due to the presence of a small Lys-rich region and a C-terminal sequence essential for posttranslational modification with a glycosylphosphatidylinositol (GPI). Phylogenetic analysis showed that is clustered together with , , and from species. expression through plant phenological stages had the highest transcription level in leaves at the seedling stage, whereas in reproductive organs there was a significant up-regulation in pistils during anthesis, also in petals 2 days post-anthesis (DPA), and in fruit at the expansion stage. Our results open future research for possible roles of AGP18 in cell expansion as a wall-associated plasticizer and reproductive processes like pistil interactions and petal cell death.
由、和基因编码的富含赖氨酸（Lys-rich）的蛋白质是与开花植物有性生殖相关的细胞壁结合糖肽。该亚类属于在模式植物（如）中广泛研究的经典阿拉伯半乳聚糖蛋白（AGP）。在本研究中，我们从甜椒（L.）中鉴定出了 cDNA，以及其在营养生长和生殖发育过程中的表达模式。推导的氨基酸序列显示，富含 Lys 的 AGP18 蛋白长度为 238 个氨基酸残基，估计分子量为 22.85 kDa，等电点为 9.7。由于存在一个小的富含 Lys 区域和一个对于糖基磷脂酰肌醇（GPI）翻译后修饰必不可少的 C 末端序列，该蛋白被预测为典型的 AGP。系统发育分析表明，与来自物种的、、和聚集在一起。在植物物候期的表达在苗期叶片中具有最高的转录水平，而在生殖器官中，在花期雌蕊中有显著上调，在花后 2 天（DPA）的花瓣中以及在膨大期的果实中也有上调。我们的结果为 AGP18 在作为细胞壁相关增塑剂的细胞扩张以及雌蕊相互作用和花瓣细胞死亡等生殖过程中的可能作用开启了未来的研究。
