Cloning, Expression And Functional Analysis Of Rice OsLTP1

Lipid transfer proteins (LTPs) are secreted proteins, which identified initially by their ability to facilitate transport of lipids in vitro from one membrane to another. Due to the absence of substrate specificity, they are currently named non-specific lipid transfer proteins (nsLTPs). Quite a number of evidences revealed that nsLTPs are probably involved in different aspects of plant physiology and cell biology, including formation of cutin monomers and embryogenesis, pathogen defense, and the adaptation of plants to various environmental conditions. However, the biological function of this protein family remains largely unknown.In our laboratory,a nsLTP1 cDNA clone, named as OsLTPl, was cloned from the roots of salt-treated Brazil upland rice (Oryza sativa cv. IAPAR 9) by SSH technique. The expression patterns of OsLTPl gene have been determined by Northern blot analysis with the materials treated under different stress conditions, including salt, PEG, ABA and cold. The expression pattern between upland rice (IAPAR9) and lowland rice (Nipponbare) was compared.The full length OsLTPl gene was also cloned via PR-PCR technique and the binary overexpression vector under control of a strong promoter uiquitin was constructed and introduced into the rice via Agrobacterium tumeficiens-mediated gene transfer. Fifty-four independent lines of putative transformants were regenerated, and PCR detection confirmed 38 of these lines have transgene integration. Northern blot analysisrevealed the independent transgenic lines have different expression level. The transgenic plant harbored the OsLTPl gene showed enhanced tolerance to the salt.