Isolation and expression analysis of a novel major latex-like protein (MLP151) gene from Panax ginseng

This is the first reports on isolation and expression analysis of a major latex-like protein (MLP151) gene in Panax ginseng C.A. Meyer. A full-length cDNA of MLP151 was 850 bp and contained a 456 bp open reading frame encoding a polypeptide of 151 amino acids. A theoretical pI value of MLP151 was 4.86 and calculated molecular weight was about 16.87 kDa. The MLP homolog proteins are found in various plants and the neighbor-joining analysis revealed that MLP151 has the closest distance with Sn-1 (bell pepper, MLP homolog gene). We analyzed the expression of MLP151 in different levels in various organs of ginseng and plantlet. In the result, the gene was low expressed in plantlet. We treated the ginseng plantlets with nine kinds of different stresses and analyzed the expression profile of MLP151. Transcript levels were significantly induced by stress treatment of light and mannitol, whereas transcript levels were drastically decreased in dark, H2O2, salicylic acid and wounding samples.