Abstract

Plant leucine-rich repeat (LRR) proteins play an important role in cell adhesion and signaling, neuronal development, disease resistance response and pathogen recognition. Therefore, the origin and evolution of the LRR genes had been studied deeply. However, there were no evidence of generating new LRR genes. In this study, the genomic and amino acid sequences of the LRR genes or proteins were aligned based on Maize GDB and NCBI databases. The result showed that the part sequences of GRMZM5G851515 and part sequences of GRMZM2G167560 were consistent with parts of GRMZM2G343449. It was indicated that GRMZM2G343449 generated from GRMZM5G851515, GRMZM2G167560 and other genes. Evolution analysis also supported that GRMZM2G343449 and homologous genes were newborn. Meanwhile, they existed in only angiosperm that is closely related to human life, suggesting that they might be retained through the artificial selection. GRMZM2G343449 and its homologous genes in Poales were an independent branch of evolution which might be related with environment adaptability because there were more diseases and insect pests in the growth and development of crops than those of other species. The results indicated that GRMZM2G343449 and its homologous genes generated from stress resistance. This study provided key information for finding new generated LRR, which might be a clue for searching newborn genes from maize and other species in the big data era currently.

Key words: Leucine-rich repeat, evolution, generation, maize