We have discussed here the phenotypic and genetic characteristics as well as proteomic analysis of lesion mimic mutants (LLM) in rice. LLM is one of the mutants that induces cell death without infection of pathogen and produces defense signaling pathways. As the phenotypic expression, most LLMs induce spots on the leaf blades and leaf sheaths at their various developmental stages. We have discussed the nature of bl1, bl2, spl1, spl3, spl4, spl5 and spl6 LLMs in rice which were formed developmentally controlled spot on the leaf blades that were appeared as tiny dotted spots during tillering stage and gradually increased up to maturity. Through Northern blot analysis lower levels of rubisco large subunit and rubisco small subunit were observed in spotted leaves (sp) compared to non-spotted leaves (nsp). However, catalase was severely degraded in the sp. Broken thylakoid membranes of mesophyll chloroplasts were seen in nsp sections and were absent in sp sections of the mutant. Through 2-DE analysis 159 protein spots were differentially expressed between wild type and mutant from identified 800 reproducibleproteins, where 114 spots were up-regulated and 45 were down-regulated. Among quantified 25 protein spots, except two, all of the protein spots including protein disulfide isomerase, transketolase, thioredoxin peroxidase, ATP synthase, and rubisco large and small subunits were identified in the wild type but were absent in the mutant. However, catalase was up-regulated in the mutant. Genetic analysis indicated that studied bl1, bl2 and spl6 mutants are controlled by a single recessive gene.

• Mohammad Nurul Matin(School of Biotechnology, Yeungnam University)
• Sang Gu Kang(School of Biotechnology, Yeungnam University) Corresponding author