Korean Ginseng Center for Most Valuable Products and Ginseng Genetic Resource Bank, Kyung Hee University, Suwon, 449-701, South Korea.
Mol Biol Rep. 2010 Oct;37(7):3445-54. doi: 10.1007/s11033-009-9936-1. Epub 2009 Nov 28.
Polygalacturonase inhibiting proteins (PGIPs) are the major defense proteins which play an important role in resistance to infection of pathogens. A putative novel gene encoding PGIP was isolated from Panax ginseng C.A. Meyer, which shows 70.3 and 68.4% homology with chick pea and Arabidopsis PGIPs. The RACE PCR was preformed to isolate the full-length PGIP cDNA from Panax ginseng. Sequence analysis revealed that the cDNA of PgPGIP is of 1,275 bp in length and that it's containing ORF encodes for a polypeptide of 366 amino acids. Domain analysis revealed that the deduced amino acid sequences of PgPGIP have a typical PGIP topology. The transcription level of PgPGIP was up-regulated in ginseng in response to wounding and infection with phytopathogenic fungi i.e., Rhizoctonia solani, Fusarium oxysporum, Phythium ultimum, Botrytis cinerea, Colletotrichum gloeosporioides and Cylindrocarpon destructans, which causes drastic damage in ginseng plants. The constitutive PgPGIP expression of 4 years old plant, showed elevated transcript level, especially roots, showed maximum then buds, stems and leaves, indicating that the gene is developmentally regulated. The crude PGIP extracts derived from the fungal infected plants directly reduces the aggressive potential of PGs from diverse group of fungi. Like other PGIPs, PgPGIP also possess board spectrum of inhibitory activity. Thus, the presence of PgPGIP gene and their active role in defense mechanism was proved. The structural model of PgPGIP was predicted based on the alignment generated by EBI-Align, the program "MOODELLER" and the predicted structure showed 10 β-strands and 10 α-helixes region.
多聚半乳糖醛酸酶抑制蛋白（PGIPs）是主要的防御蛋白，在抵抗病原体感染方面发挥着重要作用。从 Panax ginseng C.A. Meyer 中分离出一个编码 PGIP 的假定新基因，该基因与鹰嘴豆和拟南芥 PGIPs 的同源性分别为 70.3%和 68.4%。通过 RACE PCR 从人参中分离全长 PGIP cDNA。序列分析表明，PgPGIP cDNA 长 1275bp，其 ORF 编码 366 个氨基酸的多肽。结构域分析表明，推导的 PgPGIP 氨基酸序列具有典型的 PGIP 拓扑结构。PgPGIP 的转录水平在人参受到创伤和植物病原菌感染时上调，如 Rhizoctonia solani、Fusarium oxysporum、Phythium ultimum、Botrytis cinerea、Colletotrichum gloeosporioides 和 Cylindrocarpon destructans，这些病原菌会对人参造成严重破坏。4 年生植物的组成型 PgPGIP 表达，显示出转录水平升高，尤其是根部，然后是芽、茎和叶，表明该基因受发育调控。从真菌感染植物中提取的粗 PGIP 提取物直接降低了来自不同真菌群的 PG 的侵袭潜力。与其他 PGIP 一样，PgPGIP 也具有广谱的抑制活性。因此，证明了 PgPGIP 基因的存在及其在防御机制中的积极作用。根据 EBI-Align 生成的比对、“MOODELLER”程序和预测结构，预测了 PgPGIP 的结构模型，显示了 10 个β-链和 10 个α-螺旋区域。
