Abstract: To reveal the structure and function of natural rubber biosynthase interacting proteins in natural rubber biosynthesis,the total protein of latex rubber particles of Hevea brasiliensis was used as material,and an unknown functional protein containing DUF1262 domain was captured by immunoprecipitation assay using an antibody targeting CPT,a key enzyme for natural rubber biosynthesis.Bioinformatics analysis showed that there were 50 gene sequences encoding DUF1262 domain proteins in the rubber tree genome,and protein interaction network analysis suggested that DUF1262 domain proteins might be involved in signal transduction and transcriptional regulation.Fluorescence quantitative PCR results showed that the transcription of the gene encoding this protein was widely distributed in roots,leaves,flowers,branches,latex and other tissues respectively,andthe expression was low in latex and but high in bark.Salicylic acid,abscisic acid,hydrogen peroxide and drought treatment could enhance the transcription level of this gene in leaves respectively.This study demonstrated that the DUF1262 protein was involved in stress response and other physiological processes of rubber tree,providing new clues for revealing the regulation mechanism of latex biosynthesis.