유전자 침묵현상을 이용한 고추 리포옥시게네이즈 유사 유전자의 생육과 발달 관련 기능 분석

Abstract

The proteins secreted into the cell wall and extracellular space have multiple roles in plant development, metabolism, and stress responses. In a previous study, examples of such proteins secreted during pepper-pathogen interactions were isolated to elucidate their roles. Among these proteins, we further characterized a lipoxygenase homology gene CaLOP (Capsicum annuum lipoxygenase homology protein), which has a 730 bp cDNA sequence and encodes 184 amino acids. CaLOP contains a lipoxygenase homology (PLAT/LH2) domain. A database search revealed that CaLOP shares significant sequence identity with putative orthologs in other plants. CaLOP was constitutively expressed in root tissue, and was upregulated in response to TMV-P0, TMV-P2, and PepMoV viruses, as well as Phytophthora capsici. To examine the biological function of this gene in plant development, we performed in planta knockdown assays using the Tobacco rattle virus-based gene-silencing system. Silencing CaLOP in pepper resulted in abnormal growth and severe developmental disorders, including lethal phenotypes, compared with controls. Consequently, our results suggest that CaLOP may be important in plant growth and development, and pathogen defense.