Abstract:MONOCULM 1 (MOC1), a gene that is important in the regulation of plant tillering, which plays a significant role in the formation of plant axillary meristem and axillary bud. In this study, the homolog of MOC1 was cloned from sugarcane variety, which was named ScMOC1. The cDNA of ScMOC1 contains a 1299 bp ORF which encodes a secreted protein containing a GRAS conservative structure domain. The protein was predicted to encode 432 amino acid residues with a molecular mass of 45.43 kD and bioelectric point value of 6.98. Sequence alignment analysis showed ScMOC1 keep a high sequence identity with some poaceae family plants homologous proteins such as Sorghum bicolor, Leymus secalinus and Oryza sativa. In the phylogenetic tree, ScMOC1 has a closest evolutionary relationship with the homologous protein from Sorghum bicolor, Setaria italica and Zea mays. Sequenced and analysis of ScMOC1 in sugarcane varity ROC22 , totally 46 SNP and 29 InDels were identified in 30 clones. Among these variation sites, one deletion and the other 4 insertion of bases are the main causes of the changes for the gene encoding protein sequences. Neutrality tests showed that no purifying selection occurred of ScMOC1 in ROC22. Real time fluorescent quantitative-PCR (qPCR) shows that ScMOC1 was constitutively expressed in ROC22 and highest expressed in stem apex at the tillering stage; while present a expression tendency of “up-down-up-down” at the axillary buds formation and development period, so we predicted that ScMOC1 plays a role in the formation of sugarcane axillary buds. According to these researches, we speculated that ScMOC1 might play a key role in the regulation of tillering trait of sugarcane. The results obtained above will provide a theoretical foundation for function analysis of ScMOC1 and molecular assisted selection of sugarcane yield in the future.